All language subtitles for Secret.Nazi.Bases.S01E01.Hitlers.Forbidden.Island.1080p.AMZN.WEB-DL.DDP5.1.H.264-BurCyg_track3_[eng]

- As you walk through
these tunnels,

I find them to be
chilling and haunting.

- Looking at these structures

as an engineer,
it's just unreal.

- We can only assume
that what we see

is just the tip of the iceberg.

- [Narrator] 1940,
Hitler has finally

conquered a piece
of Great Britain.

An archipelago in
the English Channel

has fallen under German
rule, land that was once

characterized by quaint,
rolling English countryside

would be completely
transformed by Nazi concrete.

- 20,000 tons of concrete
and steel every single month.

- [Narrator] One island
in particular would become

irreparably marked by Hitler's
unrelenting obsession.

Transformed the isle of Guernsey

into an impregnable fortress.

- Hitler was defending
an island the way

that he would attack an island.

- [Narrator] But
for what purpose?

Why would the Third Reich
invest so many resources

into fortifying such an
insignificant island?

Was this purely an
attempt at maintaining

a foothold into
occupying Britain?

Or was there something else
that the Nazis were protecting?

- What did Hitler
have planned here?

[engaging dramatic music]

- [Narrator] Hitler sets his
sights on conquering Britain.

It would be the
country that would

unexpectedly pose the
greatest challenge.

- England was the one
country that alluded him.

They were standing alone.

The French rolled,
everyone rolled.

The United States was
not yet in the war.

This is the one country
that was opposing him.

- [Narrator] Even
under continuous attack

Britain staunchly
defended her borders,

refusing to give
ground or surrender.

That is with one small
exception, the Channel Islands.

- Guernsey is a
quaint, pastoral island

off the French coast in the
English Channel, quiet, slow.

- What could be
more British than

the rolling countryside
of the Channel Islands?

The pubs, the
winding lanes, it's

quintessential
Britain at its best.

- Beautiful countryside
surrounded by the seas,

the Channel Islands, and
then there's these beast

concrete structures almost
everywhere you look.

- You cannot visit
the island of Guernsey

without seeing the
Nazi footprint.

It's visible
everywhere even today.

The island is
filled with bunkers

and the remnants
of anti-aircrafts,

machine gun pillboxes
and observation towers.

This was really a
Nazi stronghold.

- [Patrick] Now the
island has descended

into the pinnacle
of German fortress.

It's a festung in the Nazi word.

- The materials required to
do that, the coordination

required to have the
labor force available

to make these structures
and in such a short period

of time that it's very
difficult to understand

the magnitude of this operation.

- [Narrator] By June
20th the isle of Guernsey

had been partially evacuated
and completely demilitarized.

Only 10 days after that
the occupation began.

- Long before there
was the American

shock and awe, there
was blitzkrieg.

You hit them on land,
sea, air, artillery,

infantry, cavalry,
all at the same time.

- So the British
have watched the way

that the blitzkrieg has
just rolled through France

and the Low Countries like
a knife through butter.

They know better.

They know this ground is
worthless to the Allied cause.

- Guernsey and the Channels
are symbolic but not strategic.

Yes you get a little bit
closer to Britain than France

but incrementally so
and it's irrelevant.

- And sadly for the Channel
Islands, they were given away.

Almost as a vacuum
they're left open

for the Nazis to invade.

- [Narrator] The Germans
waste little time transforming

these peaceful islands into
part of the German universe.

At first taking a soft
power approach they install

local communities,
rebuild the roads,

and amazingly switch
which side they drive on.

They changed the time
zone and currency,

and banned British radio
as a means of introducing

German culture to the island's
formerly British citizens.

- The Germans
arrived on the island

and suddenly the island
had gone from a democracy

to being occupied by a
fascist dictatorship.

- And of course the
construction work

begins almost immediately.

Hitler takes a close,
personal supervision

in making sure that the
transformation that happens

in Guernsey is exactly
in line with his vision

for the rest of Europe and
indeed the rest of the world.

- [Narrator] With little
resistance Hitler now views

Guernsey as the model
occupation, but his vision

for the island was more than
anyone could have foreseen.

- In terms of the large
fortifications built over here

the quantity that you find on
this island is unbelievable.

There was in excess of
900 large structures built

and on top of that you've got
all the smaller fortifications

that were built for
trench-line type positions.

- Hitler saw these
fortifications always

as a sign of strength, of power.

The Nazis were very into
symbolism and they weren't

going to build fortifications
and then take them down.

- And so for him,
nothing was too much.

He wanted to make sure
that the best structures

with the best engineering
was available at Guernsey.

He was not willing to take any
chances with building things

that would potentially crumble
because of some mistake.

He was just not willing
to take that chance.

- Enter Organization Todt.

- [Narrator] Just one year
after the total invasion

Hitler would task
Organization Todt to undertake

the building of some
200 strong points

on Guernsey, now
code named Gustav.

- From the Great Wall
of China to the Pyramids

the world has not
seen an organization

with this kind of track record.

They're the ones that
build the autobahn,

they build the Siegfried Line,
they build the Atlantic Wall,

it's remarkable what
this organization does.

- It is the men and more
importantly the material

to build Hitler's vision
for a thousand year Reich.

- This was warfare
that was happening

on a huge territory
right across Europe.

So to choose to implement
Organization Todt

onto Guernsey meant
something really, really big.

- The idea that they
could build fortifications

over a 1,600 mile range from
Norway to northern Spain

is unimaginable but they did it,

and they did it quickly
while fighting a war.

- [Rob] Hitler's got big,
big plans for this place.

- [Narrator] Hitler
decides the Islands

are not adequately defended.

He orders more men, more tanks,

and more defenses
to be constructed.

The island is so important
that the Inspector

of Western fortresses is
given direct supervision

of the island
fortification and required

to provide biweekly
progress reports.

- Their main concern was to
do whatever Hitler wanted.

- Hitler authorizes
an unlimited budget.

If you come in and you
say we need X number

of tons of concrete,
check we can do that.

We need X number of
tons of steel, check.

And oh in Guernsey we have
to ship it across the Channel

and the British Navy
controls the Channel.

Oh we can do that, check.

- I'm sure they questioned
whether or not all of this

was necessary but at the
same time I'm also sure

they had that technological
curiosity themselves.

- When we're building
structures today

we want efficiency
of construction.

When you look at the
structures that they built

they didn't look at
economy; it wasn't relevant.

Whatever it took
they had to throw

everything they had at it.

- [Narrator] Hitler signed off

on all plans with
the expectation

of impregnable force
within just 14 months.

- And if you were gonna do that,

that kind of thing
doesn't happen overnight.

- I can't imagine doing it then

without the tools we have today.

It seems unfathomable.

- [Narrator] Why would the
Nazis put so much effort

into something that the
British essentially abandoned?

What secrets does this
island fortress hide?

And what will it tell us about
the dark plans the Nazis had?

Though Germany has
successfully conquered most

of Western Europe, Britain
refuses to capitulate.

The blitzkrieg on
England is in full swing.

In the midst a former
tiny British island

is completely overhauled
by the occupying Germans

to become an impregnable
fortress utilizing

a stunning amount of
workforce and materials.

- Having gained such a
stronghold on Guernsey

you can understand installing
some defensive structures

to help you defend the island,

to keep you at that stronghold.

- 65 square kilometers,
you could expect

a few fortifications,
a machine gun nest,

some mines, or maybe some
batteries near the port.

- But to put together
these defensive positions

all the way around the
island, the number of troops

on there, the radar, the radio,

the communications
that they had there.

- The Islands are so small
and resource poor you're not

gonna use those to run
the Nazi war machine

across the continent of Europe.

Strategically it makes no sense.

- And remember this is
territory that is not

strategically important
for the British at all.

So it just makes you
wonder why Hitler needed

and felt it was so important

to his plans to
keep Guernsey his.

There must've been
something more.

- [Narrator] With 16,000
workers overseeing

20,000 tons of steel and
concrete being poured

and erected every month
Guernsey was turned

into one of the most
fortified islands

on Earth in just over a year.

- It's almost like Hitler
commissioned a fortress island.

- You have 12,000 German
soldiers come to the island,

thousands of forced
laborers come to the island,

all of a sudden it's
no longer your island.

It becomes very
Germanic in its feel.

- [Narrator]
Organization Todt brings

in an astounding number of
forced labor, over 16,000

ultimately and sets a
murderous construction pace.

- [Rob] The amount of labor
brought in was pretty much

one worker for every
three residents.

- Forced labor was something
the Nazis always relied on.

It was there M.O.; they
used it everywhere.

The laborers did only
what they needed to do

to stay alive and they
were worked mercilessly.

The sheer workload
working around the clock

despite the weather,
brutal conditions.

- As part of Hitler's
extreme plan for this island

and how he was gonna
achieve that, that meant

20,000 tons of
concrete and steel

being erected
every single month.

That's roughly about
how much it takes

to build, say a modern
sports stadium in a big city.

- It's a huge amount of
concrete and it's unrealistic

to put that on a 65
square kilometer island.

- You think about how
long that takes nowadays:

you're not talking months,
you're talking years.

- [Narrator] But was
the fortification

of the island truly
strategic or a product

of Hitler's paranoia
and obsession

with holding what was
once British territory?

As German bombs fall on London,

Hitler sees his model occupation

of the British Channel Islands

come under threat and
he won't allow it.

- So originally when
everything was going well

for Hitler he was planning
to invade Britain,

but now the tide of
the war is turning,

Hitler must be getting nervous.

- So Hitler must have
assumed that at some point

the British are gonna come
for Guernsey and take it back.

So he has to plan for that.

- What Hitler's done is turned

this island into an
impregnable fortress.

You can't walk more than
five meters before bumping

into some kind of armament,
or some kind of fence or post.

It literally means that
you've got line after line

of defense, heavy
artillery, pillboxes,

MG 42 rapid fire machine guns,

soldiers all around the island,

all of them looking out
waiting for the boats to come.

- And that's when
he really kicks into

the next phase of his
installments on Guernsey.

- [Narrator]
Anticipating the British

would come back to reclaim
what was once theirs

Hitler sets out to secure
Guernsey's perimeter,

starting with observation towers

that would keep an eye on the
horizon for imminent attack.

- All of a sudden there's
these big observation towers

with these thin observation
slits around them

looking like they were
almost built by aliens.

Looking very
futuristic, very bizarre

in terms of their shape and
they're haunting therefore,

and they stand out in stark
contrast to a wind-swept field,

plus the sheer size of
them, and you can understand

an observation tower
because you need to see

a certain radius and so you
get a perimeter of the island.

But these things are massive.

- Today if our intention of
those structures was just

to triangulate they'd
be really skinny

very efficient structures
maybe made out of steel

or something different but
because these were under attack

potentially they had to be
made of very thick concrete

to be able to withstand
bombing and shelling.

And so the design
considerations in a war scenario

were different than what
we might build today.

- [Rob] The original plan was
to build observation towers

around the coast of Guernsey
so they'd be able to spot

and triangulate the
exact position of any
approaching ships.

- [Patrick] The towers are
designed to work in pairs.

Soldiers positioned inside
the towers spot an enemy ship

which was what the
Germans feared would come.

They triangulate the position,

which gives their
artillery the ability

to hit those ships with
pinpoint precision.

- Triangulation is a
really important tool

that they used in
the war to identify

where a ship is and
where it might be going.

MP3 would sight where a
ship was out in the ocean

and would identify its
speed and direction.

It would relay that
information to MP4

which would have similar
data and then you could use

very simple trigonometry
and propose where that ship

may be going and how long
its gonna take to get there.

- And once they triangulate
to that position

that message would need
to get communicated

to a command center where
they could make a decision

on how they were
gonna deal with it.

- These observation
towers would have been

extremely fortified
because the destruction

of one tower would have meant
that their triangulation

would have been completely off.

- But the other thing is
the communication system.

This is a rather rural,
sleepy island from yesteryear.

They had to build a
communication system

so they could talk to
the people in the bunker,

each observation
tower could talk

to the people at the coast.

So this is a very
elaborate project.

- So for an island
that's only 65 kilometers

six observation towers of
the size that they were

would have been
overkill but I think one

of the more important
things we need to remember

is Hitler was
defending an island

the way that he would
attack an island.

- At all costs Hitler
forbade giving up

the island of Guernsey
and with the threat

of invasion feeling
ever more real

it felt that the
triangulation that was done

from the observation towers
was a little bit primitive.

It didn't act fast enough.

- They realized that
simply sighting off towers

in the middle of the bad
weather of the Channel

is never gonna be sufficient.

- [Rob] The next phase then
was to upgrade and install

stereoscopic systems
which could act much

more accurately and much
more time effectively

to defend against
any oncoming vessels.

- [Narrator] But Hitler
wasn't taking any chances.

If the enemy did end up
making it up to the beaches

of Guernsey they would
find themselves confronted

with a massive defensive array
of minefields, barbed wire,

and trenches full
of German soldiers.

- In addition to all the
fortification structures

that were built you've
also gotta bring in

all the weaponry and the
armaments that you're gonna use,

all the ammunition
that Hitler thought

would be required to
defend this island.

You gotta bring that in.

You gotta get it to all the
points around the island

and some of these guns, you know

it's not like they're packed
down into neat little boxes

that you could pop into
the back of a trailer

and head it up onto the cliffs.

These are huge guns.

The logistics again,
everything about Hitler's plans

on Guernsey just seems difficult

and it feels like a problem,

but he was insistent
it was gonna happen.

- [Narrator] The
observations and defenses

of Hitler's fortress
island all but guaranteed

the British would never
drop anchor on Guernsey.

But the Germans were taking no
chances with the Nazi prize.

They also kept an
eye to the skies.

- What the Germans
start off with

very rapidly becomes
completely obsolete.

- Manual triangulation
is somewhat primitive.

It requires math, it requires
time, and it's speculative.

That ship could change in the
course of while you're doing

your calculations and
relaying information.

- But then the Germans bring
in the best in the business,

the best radar system they
have, the Freya system.

- On MP3 the Germans
installed a Freya radar system

which was way more advanced
than the radar systems

the British had at the time.

- And it had a
technology called IFF

which was Identify
Friend or Foe,

which allowed you to
not only spot an object

but potentially tell is that
an enemy or is that a friend.

- So Hitler has taken
a proactive decision

to invest in
Guernsey once again.

- It supposedly had
a range of 100 miles.

This system could
detect any ship or plane

coming in within a long
radius to sound the alarm,

scramble the soldiers,
get them in position,

and then as soon as the
ship enters the range

of the big guns, they
just start hitting 'em.

- [Rob] These
Freya radar systems

are cutting edge technology.

These don't exist all
around the Nazi empire.

- There's always the risk in
deploying any state of the art

technology, Enigma, or
the Freya radar system,

that if the defensive
position is overrun

the enemy now has the technology

and what may have
taken you years,

teams of scientists at
a great financial burden

to develop, they
can reverse engineer

and have it almost
instantaneously.

Rationally one would think
that every Freya radar system,

every Enigma machine,
every advanced technology

needs to be along
the main French coast

where you anticipate the
D-Day, the Allied landing.

- [Narrator] And this is where

the German firepower
gets serious.

Coordinates from range
finders and radar were

to be passed Batterie Dollman,
trenches, and gun pits

housing four 220 millimeter guns

each with a range
of 22 kilometers.

- Whenever, wherever the British
decide to attack Guernsey

Hitler intends with the Dollmann
battery to be his answer,

a phenomenal
firepower capability

that will blast the British
ships out of the water.

- The firepower that
existed on Batterie Dollmann

is quite phenomenal; it had
four 220 millimeter cannons

with a range of roughly
22 kilometers each.

To put that into
perspective that's

a tenth of the way
to mainland Britain.

- They could control 360
degrees around the island.

Any ship or landing
craft that's coming

will be under a barrage of fire.

- [Rob] There are very
few ships who have guns

with the range that
Batterie Dollmann had

which would have given Hitler

a huge advantage
defending this island.

- When these guns fire there's
a huge amount of energy

behind propelling that
projectile 22 kilometers

and that force needs to
be dissipated through

the base of this gun
into the concrete

and into the earth
surrounding it.

If that gun is not
anchored down properly

to this massive
concrete the energy

will be dissipated
through deflection

and it could cause
damage to components,

and so the structure
itself is integral

to the operation of these guns.

- But it's not just big guns.

It's reinforced concrete.

There's anti-aircraft.

There's machine guns.

There's mines.

There's barbed wire and there's

a whole elaborate complex
below it for ammunition,

ventilation systems,
barracks for the soldiers.

This is probably one
of the more formidable

batteries in all of Nazi
Germany and it's on Guernsey.

- The Germans know that
when the British come,

because for them
it's when not if,

they'll be bringing the
biggest guns they have

to bear on their destroyers
and on their landing craft.

So the Germans have to
bring the best answer

they have to that,
well they brought it.

- Were those structures
built to last?

Hitler not only wants to
keep this as a strategic

as part of his of propaganda,
we're on British soil,

it was also part of a
much longer term plan

and part of his vision of
a one thousand year Reich.

So maybe that end
goal is the reason

why so much happened so quickly.

- [Presenter] But Batterie
Dollmann was just the beginning.

The Germans had far
more firepower in store

for anyone who dared cross into
Guernsey airspace or waters

and as the war effort
continued Hitler would even

start to move his
defenses underground.

Hitler has created an island
fortress out of Guernsey.

He pours more resources
proportionally

on the small, sleepy island
of no strategic importance

than almost anywhere else
on the Atlantic Wall.

The Germans have
brought in massive guns,

built fearsome
bunkers and towers,

and installed state
of the art radar,

but nothing seems
more mysterious

than the vast
tunneling underground.

- As the war progresses
the British and the Allies

make two attempts to
hit mainland Europe,

key German fortifications,
most notably at Dieppe.

That gives the Germans
every reason to believe

that the next site they're
gonna come for is Guernsey.

- Hermann Goering, the
head of the Luftwaffe

boasts that the Nazis
will control the skies.

That never happened.

The Allies controlled the
skies through much of the war.

So Hitler and the Nazis know
they're gonna get bombed.

So what's the answer? Tunnel.

- Hitler decided to
go underground because

he wanted to make sure that
his troops were protected

from any air fire,
or from any ships

that would have come
too close to the island

that could have possibly
been undetected.

- So he orders that
this enormous complex

of underground tunnels and
bunker systems are built.

He builds 29 tunnels
and down there he had

munition stores, he had
hospitals built down there,

he had its own water reservoir,
its own water supply.

By taking your defensive
operation underground

you're protecting with
the earth above you

your troops, your munition
stores, your command

or your senior command that
you'd have on the island there.

- So these are self-contained
units that can fight

even if another unit
that is supposed

to be reinforcing it or
supporting it is overrun.

- This underground
maze is almost

like an island within an island.

It is quite literally humming
and thriving with life.

- When you're
considering tunnels today

we try to limit our earthworks.

We don't want to build
tunnels if we don't have to

because they're costly,
and they're dangerous,

and penetrating the earth is
a science in and of itself.

When you look at the
scale of the tunnels

at Guernsey island,
it's massive.

There was major intent
behind these tunnels.

They were building a city.

They were building a
habitat under the earth.

Trying to fathom why they
would have gone 75 feet

underground, I can't see
a reason to go that deep,

Even if you went 10
feet underground you
would be covered.

- [Narrator] Organization
Todt put thousands to work.

Digging, laying explosives,
and carving out earth.

Forced workers from Eastern
Europe were brought in

along with conscripted
labor to build

an underground
fortress on Guernsey.

- Constructing a network
of tunnels that big

is no mean feat of engineering.

- Mining is a really
dangerous undertaking.

We have a lot of
technology today

that helps us mine safely.

Back in the war these efforts
were not well developed

and you could tell by
these fortifications

that life expenditure
was not a concern

for Hitler and the team,
building these tunnels

80 feet underground potentially
is a difficult task.

But when you tunnel
through the earth you need

to create structure to sustain

the loads imposed by the
earth above the tunnels.

We use shapes such
as arches or circles

which are very strong shapes

when they have a pressure
applied on all sides

and then they would
have to build formwork

against the tunnel
back and walls

and then they would
have to pour concrete

and let that concrete
set up before

using these tunnels for
their intended usage.

It is a very inefficient
mode of construction.

It's very slow,
it's painstaking,

and it's very dangerous.

- But each one of these
bunkers was designed

to be a self-contained unit.

- They would have had to have
their own separate systems

in order to support
their troops.

They would have had to have
their own septic system,

their own communication system.

The ventilation system
in these tunnels

was quite sophisticated,
not only to make sure

that the workers
would have had enough

to continue their jobs but also

that once the
construction was completed

that the troops
that were expected

to live down there and survive
down there had enough oxygen

to breathe and to
maintain their condition.

There were also gas
detection systems so that if

too much gas accumulated
in one location

it could easily shut
off certain sections

of the tunnel to
exhaust those areas.

- There are so many
variables to consider

when you bring
construction underground

that the problems
increase tenfold.

- [Narrator] Overall
244,000 cubic meters of rock

excavated out of all
the Channel Islands,

only a little less than the
total 255,000 cubic meters

of earth excavated for the
rest of the Atlantic Wall.

- This is no skin
deep trench system.

This is highly designed,
highly considered,

highly well-thought
underground maze.

The amount of earth that
the Germans were prepared

to dig out means that
the entire island rises

because they have
to put it somewhere.

- We're talking about several
kilometers of tunnels.

That is a lot of
excavated material.

Planning for that and
where is it gonna go,

and what are you gonna do with
it, that's another problem.

The island's
essentially growing.

Were displacing
material underground

and bringing it to the surface
and altering the landscape.

- The funny thing for
me about these tunnels

is that they weren't
necessarily joining

all of the locations
above ground.

This was effectively its own

self contained underground city

and you don't go to
those kind of lengths

unless you're
planning on staying.

- [Narrator] 16 of 29 planned
tunnels were completed

before Organization
Todt workers were sent

to fortify other areas
of the Atlantic Wall.

They left behind miles of
tunnels, a city underground,

what nefarious plans did
Hitler have for these tunnels?

And who did he imagine would
stay so long underground?

Were the tunnels merely
intended to guard against

Allied bombing or
did Hitler have plans

for these tunnels after the war?

- As you walk
through these tunnels

and think Nazi soldiers were
living here several decades ago

I find them to be
chilling and haunting.

- It's really quite
spectacular when you think

that the preparations
and the work

on these tunnels went on
for three and a half years

even as it became clear,
surely even to Hitler himself

that this island was
no longer important.

It was only when the
workers were pulled away

from the island to
go back to Europe

that the work finally stopped.

- [Rejeanne] These tunnels
are almost 80 years old

and the fact that
they're still standing

could be an
indication as to just

how superiorly they were built.

- Hitler had intended
Guernsey to be

part of his shiksha
and his destiny,

but that wasn't
having to be done.

In fact the tunnels
were eventually used

just to house injured soldiers.

- When I think about why
would you go to that effort

to take something underground,

to build a city and shelter
for people underground.

It can't be spotted from above,

that is shrouded in secrecy,

that stems from danger
really, and fear.

- [Narrator] If Hitler
wanted a propaganda tool

Guernsey was it but then
why continue to fortify it?

- There must be something
bigger going on here.

- [Narrator] If propaganda
isn't the main reason

for Hitler's island madness
what is and why go underground?

The Germans have constructed
a massive fortress

out of a quaint island
in the British Channel

fully anticipating
English forces

to come storming back
for their territory.

With eyes to the sea and
skies around Guernsey

the Germans watched and
waited for enemy attack.

With a coordinated
system of locating

and tracking enemy
boats and planes

Hitler arms the isle of
Guernsey to the teeth.

- There were 11 batteries
installed around Guernsey,

each with guns
bigger than the last,

but the most fearsome, the
most intense of them all

was Batterie Mirus right in
the center of the island.

- So the size of these
guns that were at Mirus,

which is about the
largest battery in all

of Nazi Germany's
defensive system,

the range of these guns is
over a 1000 football fields.

- Mirus, essentially has the
distance of the entire island.

It's very clear that
Hitler was taking

absolutely no chances
with Guernsey.

He's placed four of the biggest
guns he can bring to bear on

the island ready to repel the
British attack when it comes.

- [Narrator] But why
place a gun battery

so far from the coast?

How do you defend an
island from the inside?

With the biggest guns you
can get your hands on,

four fearsome gun pits
make up Batterie Mirus.

- And they were all
manned by 72 soldiers.

That is a heck of a lot of
effort for just one gun.

- You need a massive crew
to fire these kinds of guns.

You need the support systems

in terms of communication,
observation.

- [Narrator] Each gun
could turn 360 degrees

and cover a 50 kilometer range.

- With a range of 50
kilometers per gun

Mirus essentially has the
distance of the entire island.

- The drawback is how on Earth

did they get 'em to the island?

- Four Russian cannons were
captured from the Finns.

They were brought
back to Germany

where they had new
bases installed on them.

The guns were then
transported from Germany

to Saint-Malo via railroad
where they were then

lifted and put onto barges
using 100 ton cranes.

- Those barges also needed
to sustain this load

and they're traveling
across the Channel

which is susceptible
to storms and weather.

When they arrive at
Guernsey island that port

was not likely equipped to
deal with these large loads.

They probably had to build
another gantry train there

to lift these cannons off of
the barges and onto a skiff.

This skiff apparently
moved at eight kilometers

an hour, which is very slow.

The skiff had to
travel over land

all the way to the battery.

Once they had the cannons
at the site they were again

lifted into place and
set on their foundations.

- So just to place
the guns involved

an entire engineering
marvel, a logistical feat.

- That is a really big
journey for cannons.

That is a lot of
people involved,

a lot of equipment,
and a lot of planning.

- I mean the sheer operation
to bring these guns

into place is, it's gargantuan.

- All of the logistics
around the guns

and the battery
itself, the materials

that were acquired
to build that,

the cranes, the logistics,
the infrastructure,

none of that's
native to Guernsey.

All of this has had
to been installed

by the Nazis at some point.

- When you think about
the magnitude of effort

to bring these cannons
to the batteries,

to build these batteries
in the first place,

Hitler is not gonna
give up this island.

There is so much invested here.

He wants to keep this
island and I don't know why.

- I think what a lot
of the structures say

about the Nazi
Reich is something

that was very important to
them which was propaganda.

- It was part of that power that

they wanted to exercise
over the world.

- How they made their
presence known to all around.

- It's very clear
that their investment

in defending Guernsey
is absolutely critical.

- [Narrator] After a
tremendously long journey

the guns are lowered into
four 21 meter concrete pits.

Behind each pit a 31
by 31 meter bunker

containing shell cartridge
and fuel storage,

accommodation for 72 men,
and a ventilation system.

The walls were made
of reinforced concrete
two meters thick.

The gun itself was 15.8
meters long and was mounted

on an armored turret that
could rotate 360 degrees.

- You don't want to be
even possibly thinking

of approaching that
kind of battery

because quite frankly any ship
and as well as any aircraft

would have been
completely annihilated.

- Just about every naval
gun that existed at the time

would be in range of these guns.

So there's no sitting
off the coast comfortably

as the shells of your
opponent fall harmlessly

into the water; you
would come under assault.

- [Patrick] You don't
just do this for

your typical bunker or
your typical fortification.

- The Nazis fortified
almost every place they took

'cause they intended it to
be a permanent occupation.

- Something about this
island is absolutely critical

to Germany's war effort
and Germany's war vision.

- [Narrator] Test
runs of the guns

were captured on
film and sent back

to Germany for use
in German propaganda.

Hitler reveled in the optics.

Guns so powerful
they caused windows

and greenhouses in
the area to shatter.

- That's the kind
of power Hitler had
installed on Guernsey.

- And Hitler loved this.

He loved to use that
footage as propaganda

to help to show exactly
how powerful he was

to the soldiers
that he was training

as well as to the
rest of the world.

- [Narrator] If the
war was almost lost

and supplies limited this island

was no longer
remotely important.

Yet even then Hitler forbaded
surrender at any cost.

Why?

By 1943 Hitler, the
Organization Todt,

and 12,000 German
soldiers had transformed

the rugged isle of Guernsey
into an impregnable fortress.

Batteries and observation
towers guarded

the island's coast
as the forced workers

dug a complex of tunnels deep
into the the island's core,

but the Germans left
one thing above ground

until well into the war, the
one thing they overlooked.

- You know in the early
days of the blitzkrieg

the Germans were absolutely
overwhelmed with confidence.

They've had it so easy.

So when they initially
arrived they set up

their communications in
the La Collinette Hotel.

Previously it had been the
plaything for British tourists.

Now it's the center
of German activity

and military activity
on the island.

- Prior to the war
La Collinette Hotel

was a nice little
getaway for the British

to come over and get
some Channel Island sun

for the weekend perhaps
and actually not much

of that changed when the
Germans first moved in.

It was all still
quite quaint in there

but now it was
their communications

and command center for
the whole of the island.

- But if the Battle of Britain
teaches the Germans anything

it's how vulnerable
ground radar systems

and communication systems are
to air attack and bombing.

They just proved it to the RAF
during the Battle of Britain.

Once the Nazis felt La
Collinette was more vulnerable

they moved their command
center underground

into a bunker that they
built especially for it,

but this wasn't
any kind of bunker.

- [Narrator] Hidden
away in a secret bunker

was the entire Naval Command.

- The importance of this
bunker is once again

portrayed by what technology
they had down there.

This was state of the art.

They could communicate
directly with Berlin

or Paris and they
had Enigma machines

that were programmed
with their own codes

specifically for
the Channel Islands.

- [Patrick] The Naval HQ on
Guernsey becomes absolutely

critical to the German's
ability to wage war,

U-boat war on the Allies
and on Britain itself.

It's the primary
mechanism by which Hitler

intends to strangle
the British islands.

- This bunker was the center
for all the information

coming in from the U-boats
in the English Channel,

from the observation
towers above

and it was communicating
directly with Berlin

even after Paris and
France had fallen.

- [Narrator] By
1942 the Americans

had declared war on
Germany and were well

on their way to
support the British.

An Eastern front had
opened after Germany

had provoked their
former ally Russia.

Meanwhile on Guernsey
the headquarters

connecting Hitler to the Islands

remained vulnerable
above ground.

Things were changing.

In 1943 work began on a
bunker to house a new HQ.

The communication equipment
would move less than a mile

to a bunker built on the
grounds of the hotel.

- Organization Todt was
once again called upon

to oversee the building of
this secret hi-tech bunker.

This bunker's
absolutely critical.

- The Organization Todt
need to get this right.

So they bring in two industrial,
enormous concrete mixers

to pour the concrete for
a communications center,

a generator, and a
command HQ bunker.

- The bunker consisted of three
separate rooms or chambers.

One was the communications room.

A separate room to generate
its own power from and thirdly

there were the barracks
to house the high command.

- [Narrator] The
communications coming into HQ

from Berlin and France became
more and more desperate.

As the Americans
joined in the war

and a second front developed,
Hitler's high command

began to whisper about
his island madness.

- Hitler and the Nazis knew
the Allies were coming.

From '43 on they were
preparing for the invasion.

Here's an irony:
they never finished

all the gun casements
at the site of D-Day,

but they finished all the
gun casements at Guernsey.

That makes no sense.

- In his mind Hitler
must have had a bigger,

more important plan for
Guernsey and the Channel Islands

because if you think
about in the context

of everything else that's
going on it makes no sense

to put so much effort into
keeping that stronghold.

- Oh Hitler got a lot
of opposition initially

from a lot of his generals
when some still felt

like they might be able
to speak their mind.

- And within Hitler's own
high command there begin

to be whispers and murmurings
about Hitler's island madness,

why he's keeping such an
interest on this small island.

- In 1941 he was
already issuing orders

to heavily fortify and
defend the Islands,

way before any of the
work was ever done

on the Atlantic Wall and
the rest of mainland France

and extending up to the
northern reaches of Norway.

We can see that that interest
stemmed from very early days

and even when the Germans were
preparing to invade Russia

they were at that point
withdrawing artillery units

which had been designated
to attack Russia

and actually bringing
those artillery units

to Guernsey, and Jersey, and
Alderney, to defend the Islands

and the German army
high command were like

we need these units, why
are they being sent here?

- But toward the end of
the war things did change,

In one respect they
started to run out of food.

Guernsey is a small relatively
resource poor island.

So everything had
to be shipped in,

coal, fuel, food,
but the British

still control the seas
and the Germany Navy,

the Kriegsmarine was defeated.

So by the end Germany's having

a rough time
resupplying Guernsey.

They are running out of food.

German soldiers are starving.

The local islanders
are starving.

German soldiers were antsy

probably anticipating
an invasion.

They heard about D-Day
and people started to turn

on one another and it got a
little dicey toward the end.

- By 1943 it's clear to most
of Hitler's sane generals

that there's absolutely
no reason to continue

to pour so much material, so
much energy into these Islands.

That begs the
question why is Hitler

so obsessed with the
island of Guernsey?

- [Narrator] The tides
of the war had turned.

German troops battened
down the hatches

and waited for news
from Paris and Berlin.

In the coming months and
even after it had become

clear the Germans
had lost the war,

Hitler would hold onto this
island with everything he had.

All of this for 65 square
kilometers of farmland.

Hitler's island
madness has transformed

a small island in
the British Channel

to a monstrous fortress
bristling with armament.

In less than five years the
island has been fortified

using 616,000 cubic meters
of steel and concrete,

about 10% of the materials used
in the entire Atlantic Wall.

Observation towers
and 11 batteries guard

the Guernsey coastlines
and Enigma machines

sending coded messages
to nearby U-boats,

other Channel
Islands, and Berlin.

After the war when
deported islanders returned

to their island home
they'll find it marred

by evidence of Hitler's mania.

It's a far cry from the quaint
island in the British Channel

whose economy was based
on tomatoes and tourism.

- The invasion Hitler feared for

so long actually never came.

Even on D-Day the
Channel Islands were
completely bypassed,

flown over, the boats
circumnavigated it.

- As the war progressed
and the tides turned

for the Germans they continued

to pour resources into Guernsey
island which seems strange.

There were so many fronts
that needed attention

and the resources required
here were substantial.

- And the irony is that
Guernsey's never invaded.

It never plays a
role in World War II.

It becomes almost
an afterthought.

It's folly.

- These enormous
artillery pieces,

these heavy rapid
fire machine guns,

they're all whispering
in the wind.

They're all standing silent
because the Allies don't come.

Hitler got it wrong.

Instead he leaves over 12,000
soldiers trapped on the island

bypassed when the Allies
make their move on Normandy.

- Hitler's madness about
Guernsey, his obsession

led in part to the
Nazi undoing at D-Day.

More defenses should've been
built along the French coast

proper rather than on
a tiny island offshore.

- When supply lines were
cut off from Guernsey

and the troops and the residents

were starving on the
Islands, even then

Hitler insisted
that it be defended.

- If Hitler had not been
so obsessed with Guernsey

and if had put the emphasis,
the amount of guns,

construction, time, and energy,
and soldiers from Guernsey

at Normandy you would have
had 12,000 more soldiers,

dozens and dozens more
massive guns, bunkers, mines,

so by him focusing so much
on Guernsey it helped us

to take D-Day in a
little less bloody way.

- [Narrator] Was Hitler's
refusal to give up the Islands

lunacy from a mad
dictator in decline?

What dream was he
desperately clinging to?

- Guernsey remains a mystery.

There is no rational or good
explanation why Hitler devoted

so many resources to this
tiny, insignificant island.

- Even today when you see what's
left of the fortifications

that were installed on Guernsey,
the way there were designed

and built tells you that
this was not just a temporary

defensive mechanism that
Hitler wanted to install.

Hitler had intended
Guernsey to become

an impenetrable
fortress, the vanguard

of his thousand year Reich.

- Thankfully that never
actually materialized.

- Instead it became
a slowly corroding

testament to his island madness,

the only time that he got
a foothold on British soil.

- And to the bitter end
though it was in Nazi hands.

- [Narrator] Though
Guernsey would eventually

be given up without
a fight, Hitler

would not live to
see its surrender.

10 days after Hitler took
a fatal dose of cyanide

and a full 24 hours
after HQ got the message

the war was over German
forces surrendered

aboard the HMS Bulldog
in St. Peter Port.

But what if the war
had gone the other way?

If the Channel Islands had
been only the beginning

in Germany's occupation
of British territory?

What would have become
of Pleinmont, Mirus,

and all these
underground structures?

We may never know what dark

plans the Nazis
had for Guernsey.

Was it a toehold
on his enemy's land

that Hitler simply refused
to give up at all costs?

Was it part of a longer
term strategic plan

we haven't been able to unearth?

Those secrets lie buried
under decaying structures,

symptoms of a terrifying
dream and dark time.

[dark engaging music]