Today, it's one of Europe's largest democracies
and greatest military powers.
But standing at the crossroads between continents,
Spain has repeatedly faced invasions from both
inside and outside Europe.
It has been the battleground for conflict over land,
wealth, and more than anything, ideas.
This is the extraordinary story of the defense of Spain.
From centuries of religious struggle.
It would seem like they're now caught in
a trap where they would be utterly destroyed.
Through vicious battles to protect
the riches of its empire.
When they finish their terror attack on the city,
Cádiz lay in ruins.
All leading to one of the most bitter civil wars
of the 20th century.
People started pouring into the tunnels.
Thousands of men, women, children, the elderly,
just trying to escape the nightmare above their heads.
Every country is a prisoner of its geography,
bordered by mountains, rivers, seas, or stone.
And every country must defend these borders from attack.
On land, in the air, and on the high seas.
This series explores the incredible structures,
ingenious weapons, and brilliant strategies
that have shaped Europe's most battle-hardened countries
over the last thousand years, and played a crucial role
in creating the nations we see today.
The vast castles, palaces, and cathedrals of Spain
are amongst the grandest and most exotic in Europe.
Striking monuments that whisper the epic history of a nation.
Its very soul forged in brutal conflict
under two mighty empires.
Lying to Europe's far southwest, Spain occupies most of
the Iberian Peninsula, almost touching the
northern tip of Africa.
1,300 years ago, it stood at the frontier of the largest empire
the world had yet seen.
A mighty Islamic caliphate, stretching from Central Asia
all the way to the Straits of Gibraltar.
Where in 711, the caliphate launched an invasion
that would change Spain forever.
Armies of several thousand Islamic warriors
made a grab for Spain's fertile land and vast mineral resources.
Within a few years, the invaders had claimed
most of the Iberian Peninsula for the Caliphate.
It was just the beginning of a long conflict
between Christian Europe and the North African invaders.
Historian, Dr. Onyeka Onubia has come to Southwest Spain,
the heart of Islamic power, to investigate the tactics
and battles in this struggle.
The people that came from Africa and Asia Minor
are colloquially called Moors, and they were to rule large
parts of the Iberian Peninsula for almost eight centuries.
They called their kingdom Al-Andalus.
And the Moors brought with them to Al-Andalus,
a sophisticated new culture.
What was it to live under Moorish culture?
Well, this culture was a synthesis of ancient Greek,
ancient Roman, African mores, with Islamic Muslim traditions
all mixed in together.
And what you see here with running water
and underground heating is an indication
of that civilization, that opulence, that finery,
perhaps some of the most advanced civilization
that was existing in Western Europe at this time.
But whilst in the South,
Islamic Spain flourished and grew rich.
To the North, Christian armies began taking back territory.
Al-Andalus also became vulnerable to growing threats of
invasion from the sea.
In the struggle for the survival of Islamic Spain,
one place would prove critical, a lucrative trade link
connecting Al-Andalus to the rest of the Muslim
world and the Mediterranean, the southern port of Malaga.
In 1057, Malaga was under the control of
an ambitious Islamic warlord,
the Emir of Granada, Badis Ibn Habus.
And his number one priority was to defend this vital port.
Ibn Habus needed to build a
place that was strong geographically,
strategically, militarily.
A fort that would be impregnable.
His solution was the Alcazaba.
Perched on a hill on the
southeastern edge of the city,
the Alcazaba overlooks the port and dominates its surroundings.
Geographically, it's in a strong position.
Attack, if it came, would be seen
from everywhere in the citadel.
But it is the defensive design of this citadel
that makes it unique.
It had two tiers, a high outer wall with
regularly spaced towers,
and a fortified inner enclosure that protected the palace.
Even if assailants penetrated the heavily fortified entrance,
they would find themselves in a maze-like passageway,
facing a series of strong gates.
An attacking force needs momentum, speed,
in order to take a castle like this.
This design, with its sharp turns and bends
and close quarters, prevents that momentum.
The attacking force never gets the speed
that it needs to conquer this citadel.
But the biggest danger would come from above.
The attacking army would be met by spears,
boiling oil, waste, or the defender's main weapon,
the short bow and the crossbow.
Crossbows were easy to use
and deadly accurate at short range.
With the battlements providing protection for reloading,
the short bow and skilled hands was ideal for rapid shooting,
the perfect weapons for defending the citadel.
As the attackers emerged into the open courtyard,
they would run into a murderous hail of bolts and arrows
coming from every angle.
High up on these walls,
the genius of Ibn Habus's design is clear.
We have towers, turrets, and walkways
protecting other towers,
turrets, and walkways in intersecting arcs of fire.
Any attacker is being met by not just one,
but several lines of defense.
It's genius.
It was a sort of lethal medieval computer game
with increasing levels of impossibility.
The people that constructed these palaces
must have felt that they were beyond attack,
safe and secure in their citadel of power.
The defenses of the Alcazaba was so formidable
that in its first 400 years, there was not a single
attempt to lay siege to it.
But its day of reckoning was coming.
The Christian armies continued a gradual advance south
until by the 15th century, all that was left of Al-Andalus
was the Emirate of Granada.
Governed from Granada's sumptuous Alhambra Palace,
Islamic Spain was about to face its sternest test.
The armies of Christian monarchs,
King Ferdinand and Queen Isabella,
now outnumbered those of the Moors,
and they were coming for Malaga.
With them, they brought state-of-the-art
weaponry, artillery, with the power to fire into
the very heart of its citadels.
In May 1487, the armies of Ferdinand and Isabella
surrounded the city of Malaga with 80,000 troops,
and the largest artillery Spain had ever seen.
They blockaded the port so that no one and no supplies
could get in or out,
and then demanded that the Moors surrender.
But the leaders of just 15,000 Moorish defenders,
hardened and charismatic, Hamet el-Zagri, refused,
and he had reason to be confident.
The Moors had updated Malaga's defenses with an imposing wall
up to four meters thick around the city,
and an extra outer wall to protect against attack
from the north.
But el-Zagri's secret weapon lay to the east,
where a steep hill offered a strategic vantage point.
Here, the Moors had constructed a secondary,
highly fortified castle, overseeing and towering
above the Alcazaba, the Castle of Gibralfaro
Gibralfaro was really state-of-the-art.
El-Zagri's biggest advantage was that this fortification
had been constructed with modern technology in mind,
with the knowledge that they may be attacked
with gunpowder, cannons, and guns.
Look around and see that we're in an elevated position,
high up on this mountain.
This position is strategically important
because it holds the higher ground.
This meant the defenders in Gibralfaro
could take potshots at an attacking army all day long,
whilst the attackers would be helpless
to do anything about it.
The parapets and towers were constructed
with a particular elevation, making it impossible for
Ferdinand or Isabella's cannons or guns to reach the top.
Malaga had the strongest fortifications
in all Al-Andalus.
But it faced the greatest firepower
the country had ever seen.
The future of Spain, of Islam and Christianity
hung on the coming battle.
And it began with large batteries of
Ferdinand's cannons opening fire.
After weeks of bombardment,
they finally breached the outer wall.
The Moors fought fiercely to keep Ferdinand's troops out.
But eventually, they were forced to retreat
behind the main city wall.
It would seem like the defenders are
now caught in a trap
where they would be utterly destroyed.
Now, Ferdinand brought in a new weapon,
his heavy Lombard cannons,
firing 30 kilogram iron shot to try and
smash Malaga's main city walls.
But the walls held firm.
Still refusing to surrender, El Zegri launched raids to
terrorize the Christian camps.
So the Christians decided to escalate.
And in Queen Isabella, they had a mastermind
of logistics to do it.
They brought in thousands more troops and mobile siege towers.
In response, the Moors dug underneath the towers
and blew them up.
But however fiercely the Moors fought,
they could not break the blockade.
The attackers managed to stop
the importation of food and the water ran out.
Finally, after three months of fighting,
Ferdinand destroyed the tower guarding
a key bridge to the city,
allowing the Christian troops to pour in.
By now, the citizens of Malaga had resorted
to eating cats, dogs, and leaves.
And on the 13th of August, they threw themselves on the
mercy of Ferdinand and Isabella.
But El Zagri and his troops in the Alcazaba
refused to surrender,
still hoping for reinforcements to arrive.
Against the odds, they fought on.
Eventually, the defenders in Alcazaba
were forced to move from their position
up here to Gibralfaro.
The Alcazaba was connected to Gibralfaro
by a fortified corridor called the Coracha.
The Coracha was an escape route where soldiers and
weapons could be moved in a time of withdrawal
from one citadel to another.
El Zegri's men climbed the Coracha to Gibralfaro.
There, the enemy threw everything at them,
but they couldn't break the defences.
El Zegri held out inside the fortress complex
for about a week, but in the end, it wasn't the
fortifications that failed.
His reinforcements never arrived.
Ferdinand had destroyed them before they got to Malaga.
When El Zegri realised this, he had no choice.
On 19th August 1487, he finally surrendered.
Most of his troops and the citizens of Malaga
were sold as slaves.
El Zegri himself died in jail.
Around Malaga, the Muslim symbol of the crescent moon
was replaced with that of the cross.
The small mosque in Gibralfaro was consecrated
as a Christian chapel.
But it would take Ferdinand and Isabella another five long years
of bloody fighting, until in 1492, they
finally captured Granada.
After nearly 800 years, all of Spain was Christian once again.
But this power couple were only just beginning their conquests.
The very same year, they made a momentous decision
and took a gamble to finance a young sailor
called Christopher Columbus.
To search for a route to India by going west.
Out of the ashes of the Islamic Caliphate,
a new empire was about to rise.
The Spanish Empire.
In October 1492, Christopher Columbus landed
in the Bahamas with just three small ships.
A seismic event that was to catapult Spain
to the status of world superpower.
Its new empire soon spread through the Caribbean
and large swathes of North and South America.
For the indigenous peoples, though, it was catastrophic.
Along with modernisation and a new religion came enslavement.
Millions died through war and disease,
whilst the Spanish took vast
quantities of gold and silver back to the mother country.
Most of this treasure came through
the Atlantic port of Cádiz, a city precariously positioned at
the tip of a narrow peninsula.
Historian Claudio Lozano has been investigating
how these riches also made Cádiz vulnerable to Spain's enemies.
The moment that you are bringing all this
wealth from the New World,
and also not only the wealth, but also all the mythology
about El Dorado and about a really wealthy New World,
I mean, all the landing points, specifically Cádiz,
become a target immediately.
The worst attack on Cádiz came in 1596,
during a bitter two-decade-long war
with newly Protestant England and Holland.
150 ships plus 15,000 men under
command of Queen Elizabeth I.
At dawn on Sunday 30th June,
the guns of the English Royal Navy
opened fire on the Spanish warships guarding the
treasure fleet in the bay.
Cádiz's gun batteries and warships were
unable to stop the attackers,
who entered the bay and ran amok amongst the treasure fleet.
Then they broke into the city and ransacked it.
Their crew rampages across the city,
burning every single building,
looting whatever treasure they could.
Imagine the terror of the people living here,
seeing their city burning,
their loved ones being killed
and everything of value stolen from them.
When they finished their terror attack on the city,
Cádiz lay in ruins.
It was a disaster for Spain.
The loss of Cádiz threatened her
supply routes and the empire itself.
The Spanish were forced to make a choice -
either protect Cádiz or abandon it.
So the King of Spain decided on an ambitious plan to rebuild it
under the country's foremost
military engineer, Cristóbal de Rojas.
To make Cádiz impregnable, de Rojas adopted
the latest ideas from European state-of-the-art fortresses.
First, to guard the city against attack from the sea,
he constructed a star-shaped fort,
Castillo de Santa Catalina.
Its pointed bastions armed for
defensive fire in all directions.
The bay itself was shielded by a natural gateway,
back then with no bridge crossing it.
De Rojas designed two new forts to guard it.
On the east bank, Castillo Matagorda.
On the west bank, Castillo Puntales.
Between them, these forts gave the Spanish complete control
over the sea routes in and out of the bay.
To protect its citizens, Cadiz's own defenses
were extended with a thick, heavily armed curtain wall.
Cádiz defenses against sea attack
were the most ambitious military work in the country,
transforming the city into one of the best protected in Spain.
Over the next two centuries,
Cádiz faced a series of attacks by England and her allies.
But thanks to its robust fortifications,
none of them managed to break through to the city or the bay.
Cádiz seemed impregnable, and Spain's empire continued
to flourish right up until the end of the 18th century.
But a new threat was coming,
from a growing empire to the north.
And the whole of Spain would depend
on the fortifications of Cádiz for its survival.
In 1803, the Napoleonic Wars began.
To start with, Spain supported France
against Britain and Portugal.
But that was to change dramatically
when Napoleon decided to invade Spain.
In 1808, the Spanish government fled Madrid,
moving first to Seville, then retreating all the way to Cádiz.
So Cádiz was the last hope
to recover the independence of Spain.
Could Cádiz now defend itself
against an attack from the land by Napoleon's mighty army?
Since the 1500s, the formidable Puerta de Tierra, or Land Gate,
dominated the approach to the city.
But it was breached during the English attack of 1596.
So Cristóbal de Rojas had to improve the land fortifications.
He designed giant zigzagging bastions, interspersed with deep
ditches and sloping ramparts.
A terrifying challenge for any invader.
And even if, as was common,
the attackers deployed miners to dig under the walls,
they'd be in for a shock.
Caving expert Eugenio Belgrano is taking Claudio to see
Cádiz's secret underground weapon.
During the 18th century, the Spanish built a web
of three kilometres of tunnels underneath the fortifications.
These tunnels had small rooms that we called 'hornillos'
which were filled with gunpowder.
When the engineer knew that the enemy tunnel was getting close
they would blow up this whole tunnel
making it impossible to lay siege to the city of Cadiz.
It's very impressive for me
that underground defence, combined with
the ground defence, made the city completely impregnable.
The French discovered that not only
was the Land Gate impregnable, the bay was now swarming with
warships of Spain's new ally, Britain.
Their best chance was to approach from
the opposite side of the bay, along the Trocadero Peninsula,
for a surprise assault on Fort Matagorda,
which was not equipped for an attack from the land.
British reinforcements were summoned to defend the fort.
A company of the 94th Regiment of Foot
were scrambled to ferry arms and men across the bay.
But it wasn't enough.
All the efforts were futile,
due to the overwhelming power of the French artillery.
The French had brought up
30 heavy-caliber guns, firing 24-pound shots,
giving the defending garrison of 140 men little chance.
The battle was a blow for the defenders.
Half of them were wounded or killed.
And the remaining men were forced to retreat.
But even with the French in Matagorda,
the residents of Cadiz, over three kilometres away,
were out of range of their guns,
and protected by the Royal Navy.
So Napoleon's engineers hatched an audacious plan -
to build a new weapon with a much greater
range than any other cannon in existence.
Fort Matagorda itself is no more,
but close to where it once stood,
there remain enormous concrete footings.
A series of platforms to support
10 giant howitzer cannons of 8 inches calibre,
and with a range of up to five kilometres,
easily enough to reach Cadiz.
They were known as Grand Mortars.
Now the French unleashed a massive bombardment of huge
exploding grenades on Cadiz.
But this technology was untried.
The Grand Mortar was very powerful,
but was inaccurate.
Many of the shells never exploded.
Even one of the shells fell into the city,
into a crowded place, and nobody was injured.
The siege continued for eight months,
but Cadiz remained impregnable.
Well supplied and heavily armed,
it even sent regular sallies of guerrillas
to disrupt the French supply lines.
Across Spain, guerrilla attacks like this became
an increasing nightmare for Napoleon.
To the north, aided by the Portuguese and British,
they pushed the French back,
threatening to cut off Napoleon's forces around Cadiz.
So, on the 24th of August 1812, the French besiegers finally
packed up and headed home.
Spain's government had been protected.
Cadiz was the only city in Western Europe to
hold out against Napoleon's attack.
All the defences worked perfectly.
I find that very impressive.
Cadiz resisted.
The Peninsula War was the last time that
a foreign power would occupy Spain.
But the conflict left the country shattered.
The next century would see it
tear itself apart over very different ideas
of what a modern Spain should be.
Following the Napoleonic Wars,
the Spanish Empire began to collapse.
And by the early 20th century,
there was virtually nothing left.
Without the riches that the Empire brought,
Spain was reduced to one of the
poorest agrarian economies in Europe.
Conflict grew between those who favoured
modern ideas like democracy or socialism,
and those who yearned for the
glorious past of a powerful empire,
a strong church and a strong authoritarian state.
In 1936, right-wing nationalist rebels led by Francisco Franco
launched a military coup against the socialist republican
government under Manuel Azana.
A polarised nation was sucked into a vicious civil war.
Urban areas in the south-east largely sided
with Azana's republican government,
whilst the more conservative north and south-west mainly
supported Franco's nationalists.
One republican-supporting town would
become infamous for a new type of warfare,
first seen during the Spanish Civil War - Guernica.
It was the afternoon of Monday 26th April 1937 - Market Day.
The main square was packed when the church bells of
Santa Maria sounded the alarm.
Nationalist aircraft darkened the skies above.
Over three hours, 50 tons of high-explosive and
incendiary bombs rained down,
flattening three-quarters of the town.
Those who tried to escape were mercilessly
strafed by fighter planes.
Hundreds were killed and injured.
The horror of the attack was captured
in Picasso's shocking painting, "Guernica".
And Guernica was just one of many.
The Spanish Civil War would be the first war in history
that featured systemic carpet bombing of civilians.
And it happened right across the country.
Former Marine Arthur Williams is a military historian and pilot,
who's come to southern Spain to investigate the bombings
and the extraordinary response of the civilian population here.
It's hard to picture on an
ordinary day like this, all these years later,
how the thousands of people going
about their busy day-to-day lives
would have defended themselves against an unannounced attack
when bombs started falling from the sky and shells started
exploding in random places.
You can only imagine the bloody chaos
and confusion that would have ensued.
But how did a rebel like Franco
get his hands on these machines?
The aircraft were supplied by Nazi Germany and Fascist Italy.
Both saw a strategic advantage in neutralising Spain
for any future conflict.
The German planes were known as the Condor Legion
and displayed nationalist diagonal crosses on their wings.
They were a new generation of aircraft,
which would soon become terrifying
Nazi icons of the Second World War.
And enabling this death from the skies, a new fighter,
one of the planes that strafed civilians
on that day in Guernica.
This is the Messerschmitt BF-109,
and it was one of the most important aircraft
in the history of military aviation.
Only a few months after its maiden flight,
three BF-109s were sent to Spain for real-world testing.
And when the aircraft was introduced,
it was the most advanced fighter of its day.
The Germans brought around 150 of them
to fight during the Spanish Civil War.
Its revolutionary light airframe and slim wings
gave it a speed and maneuvrability that in 1936
made it the most feared fighter in the world.
By contrast, the Republican Air Force had a smaller number of
Soviet and obsolete aircraft that just couldn't compete.
The BF-109 supported bombers
on a vast number of air attacks
that targeted the civilian population all over Spain.
The aircraft's air superiority was key to the devastating
impact that those raids had.
But in some cities, civilians organised themselves
to defend against the attacks.
And here in the southern city of Almeria,
they came up with something extraordinary.
To uncover this masterpiece of defence,
we need to go underground.
Underneath Almeria's streets lie almost
five kilometres of subterranean passages,
known locally as the 'Refugios'.
But what's fascinating about these tunnels
is that it's not a military building.
It's not about protecting soldiers or
helping a counter-offensive.
It's purely for saving the lives of ordinary people.
It took a huge communal effort.
From January 1937, hundreds of volunteers helped professional
miners to dig these tunnels.
They excavated these tunnels by hand,
using just picks and shovels.
The workers toiled under intense
time pressure to finish, knowing that disaster
could come from the sky at any moment.
But barely a few months
into the monumental task, the Refugios
would come under its greatest test, in what would be one of
the most shocking events of the Civil War.
On the 29th of May 1937,
off the coast of the Spanish island Ibiza,
Soviet pilots flying bombers
for the Spanish government spotted a target,
identified as a nationalist battle cruiser.
Only after hitting it and killing or
wounding around a hundred sailors
did they discover their mistake.
It was a non-combatant German warship on patrol
the Deutschland.
Hitler was furious and decided to take revenge
on the republican city of Almeria.
At dawn on May 31st, just over four months
after its construction began,
Almeria's public air raid shelter,
only one quarter built, was called into action.
German warships moored along
the coast opened fire on the city.
People started pouring into the tunnels,
desperately trying to seek refuge from
the hell that was unfolding above ground.
Hundreds of heavy naval shells rained down
on Almeria, destroying 200 buildings.
You've got to try to picture
what it would have been like down
in these claustrophobic spaces, with thousands of people -
men, women, children, the elderly
stifling conditions, just trying to
escape the nightmare above their heads.
The only defence they had was nine metres of soil.
Forty civilians were killed,
but it might have been hundreds
had it not been for the Refugios.
As soon as the coast was clear, the labourers had to get back to
tunnelling their way through the city.
The shelters were designed as a life support system,
connected to the services above ground.
One of the most ingenious aspects
of design for these shelters is the fact that they tapped into
the city's already existing infrastructure
to support the thousands of people
that were taking refuge down here.
So, for example, of course, humans need
food and fresh water to survive,
and so you'll find that the tunnels run underneath the
city's existing market square.
Stairwells connected the food market
and also the local hospital to the shelters.
Doctors and the nurses, as soon as the
balloon goes up and the air raids start,
they can bring their patients and medical supplies
and anything they need
right down here really, really quickly.
This was geared up to be a fully functioning operating theatre,
and, of course, they needed that
because there are bombs dropping above ground.
You know, you've got casualties coming down
here at a rapid rate, so they've got to cater for that.
It's impossible to gauge the psychological damage
to the civilians being bombed,
but there is a hint in these tunnels
of how it affected children.
If we have a look on this pillar,
you can see crude graffiti depicting the scenes of the day.
Here we've got several aircraft.
Look, there's four of them coming towards us.
There's the propellers, the undercarriage.
And then this is a house.
Presumably, these marks here are the shells coming into the city.
Here you've got children drawing what they
see, and these are warplanes, overhouses and
warships shelling their town.
And in the innocence of youth,
they've just captured a moment in time.
From the beginning of the construction of
the Refugios until the end of the war,
Almeria suffered around 40 aerial bombing raids.
The shelters may have saved thousands of lives.
The Refugios tunnels aren't a fort or a castle.
They're not designed to house superweapons or give soldiers
a tactical military advantage.
They're purpose-built to protect the lives of innocent civilians.
And that has to make them one of the most impressive defensive
systems anywhere in Europe.
Thanks largely to their air superiority,
the nationalists edge towards victory.
And on 31st March 1939, Almeria, one of the last republican
strongholds, was forced to surrender.
Its citizens emerged from their underground shelters,
safe, but to news of a total nationalist victory.
After the war, Almeria's Refugios were
largely forgotten for nearly 60 years.
By the time they were reopened,
Franco's militaristic regime was long gone.
Today, Spain is still dealing with national differences.
But has transformed peacefully into a progressive democracy.
A place where conflicting ideas are more likely to be dealt
with by dialogue than violence.
Its military has stood back from
politics and is once again global-looking.
But instead of protecting treasure fleets,
it takes part in security operations under NATO,
the European Union and the United Nations.