(dramatic music) (narrator) The Berlin Wall.

For almost 30 years, it divided a country.

It separated families and destroyed lives.

To attempt to breach it was to risk death.

(speaking German) (beeping) (narrator) Both its secretly planned construction and its sudden fall were preceded by events that were like a countdown in an intense race.

(speaking German) ♪ (narrator) Numerous personal accounts, journal entries, and letters reveal the true dimensions of the division of Germany.

♪ (indistinct announcement) (soft music) ♪ October 27th, 1961.

Berlin.

One of the most perilous junctures of the Cold War era.

Just ten weeks after the Wall had gone up, Soviet and American tanks faced off at the Checkpoint Charlie border crossing.

Onlookers lining the streets feared that war was imminent.

The showdown of the systems became a media spectacle.

♪ (Dieter) I was up on a balcony at the time and had a view of the whole street over into the East as well as back down into the West.

I realized then that the situation was very, very serious.

(dark music) (narrator) For the first time since the building of the Berlin Wall, the Cold War took on a whole new dimension.

During these hours, diplomatic lines between Moscow and Washington ran red hot.

Would the superpowers actually risk war over Berlin?

♪ It was an attempt by the Americans to test how far the Soviets would go.

So it came to this big showdown.

Who'd keep his cool?

Who'd blink first?

That was 200 meters away from the Third World War.

If anything had happened there, if a tank had fired a shot, it would have brought immediate disaster.

(clicking) ♪ (mellow music) (train chuffing) (narrator) August 1960.

Precisely one year before the Wall was erected, Berlin was already divided.

But crossing the borders between the East and West sectors was a regular feature of daily life.

Two opposing political systems attempted to coexist in the same city.

(indistinct chatter) (speaking German) (soft music) ♪ (Kati) The problem was that many people enjoyed the advantages of the GDR and the advantages of West Berlin at the same time.

They lived cheeky in East Berlin, paid maybe 60 marks rent.

Then, they went over to the West to work, exchanged their money at a rate of 1:4, then came back over to the East.

Of course, they earned a whole lot more than the people who stayed in the GDR.

(guitar music) (narrator) A situation that led to tension.

The Western zone of the city offered better pay and a higher standard of living.

That awakened aspiration in residents of the East.

From February to May alone, over 20,000 people took advantage of the Berlin escape hatch to leave socialist East Germany for the West.

(Ilko-Sascha) It wasn't that dangerous to get from East Berlin to West Berlin, whether you were going over to see a play or a movie or to flee for good.

Later, on the inner-German green border, a low-risk crossing was no longer possible.

(tapping of typewriter keys) ("Brigitte Reimann") Lutz has gone with Gretchen and Krümel to the West.

He is at this moment just two or three kilometers away and, yet, out of reach in the refugee camp at Marienfelde.

(soft music) I feel for the first time with pain, not just intellectually, the tragedy of our two Germanys.

(tapping of typewriter keys) ♪ (clicking) (narrator) In letters and journal entries, East German author Brigitte Reimann reflected on the situation in divided post-war Germany.

(somber music) While she was fully engaged in establishing socialism in the German Democratic Republic, her beloved brother Ludwig Lutz Reimann decided to flee to the West.

♪ (Ludwig) Traveling from Magdeburg to Berlin, you could choose a train that ended in Potsdam instead of circling around West Berlin.

From Potsdam you'd then take the S-bahn, which took you right through the West.

And we happened to come to a stop, Bahnhof Zoo, the last in the West, and we decided to get out now.

(soft music) (clicking) ♪ (narrator) Done by the growing exodus of its citizens via West Berlin, the East German government devised a response aimed at undermining the morale of the West.

From September 8th, 1960, they began to demand an entry visa from West Germans and West Berliners wishing to enter East Berlin.

The document had to be issued beforehand by the GDR People's Police.

From September 23rd, this constraint was extended to include diplomats of the Allied forces.

♪ (Frederick) Well, it's the game of poker.

All these--all these threats, restrictions, niggling little... ♪ ...attempts to make life more difficult for outsiders to come into East Berlin.

So, all these things were in the nature of that.

They were a gradual and quite insidious growth in the exercise of power which was Ulbricht's speciality.

The phrase "salami slicing" comes with this, and he was an expert salami slicer.

(narrator) On September 12th, 1960, Walter Ulbricht officially took the helm of the German Democratic Republic.

As Chairman of the Central Committee of the Socialist Unity Party, he had already unofficially held the reins of power.

A rigorous ideologue, Ulbricht was not inclined towards a liberal political course for East Germany.

(Frederick) He was in his way, I think, a nationalist.

And he wanted to build an East Germany that reflected what he thought the country ought to look like.

(narrator) Meanwhile in West Germany, Ulbricht's opposite number Chancellor Konrad Adenauer turned his attentions to the Western Alliance.

He had resigned himself to the German division.

Reunification seemed out of the question as long as the two sides of Germany were so strictly aligned with opposing blocks.

(moody music) ("Konrad Adenauer") For us there is no doubt that we belong to the western European world.

We want to maintain good relations with all countries, but especially with our neighbors, the Benelux nations, France, Italy, England, and the Nordic countries.

(Frederick) Konrad Adenauer was Catholic.

He was conservative in a relatively easygoing kind of way.

He viewed Germany east of the Elbe as semi-Asiatic, as he made perfectly clear on several occasions.

And it was also largely inhabited by Protestants and Socialists.

These were not people that Konrad Adenauer felt much sympathy for.

(narrator) And Adenauer also disapproved of the special status of the divided city of Berlin.

He felt the Western allies should not have extended their trust to the Soviet Union.

(dark music) ♪ When the "Big Three," Churchill, Roosevelt and Stalin, met at the Black Sea resort of Yalta in February 1945, Nazi Germany was already close to capitulation.

The victors agreed to divide the vanquished nation into four zones of occupation.

Though the capital Berlin was in the Soviet zone it was to be ruled jointly by the Allies.

The result was the four occupied sectors.

The three Western zones were soon like an island in the middle of Soviet-controlled terrain.

♪ (Matthias) No one saw the problem coming because the attitude was everyone now has a right to a sovereign zone in the prewar capital, Berlin.

They were the victors, and occupying the capital was a demonstration of that.

But that two rival systems, arch enemies actually, would later engage in a confrontation.

I don't think anyone but Stalin foresaw that at the time.

(narrator) On June 20th, 1948, the Deutschmark became the official currency in the Western sector of Berlin.

Realizing that the West aimed to retain its Berlin stronghold, Soviet dictator Stalin instigated a blackout in the Western zones.

♪ The Berlin Blockade began.

British and American Allied forces acted quickly, organizing the now famous Berlin Airlift operation to deliver vital supplies to West Berlin.

That July, airplanes already managed to deliver 70,000 tons of freight to Berlin.

West Berliners extolled the British and Americans as valiant protectors.

The Kremlin had assumed that an airlift would never be able to supply a vast city of several million inhabitants.

(somber music) (Matthias) Stalin had simply underestimated the will of the Western Allies to stand up for that part of Berlin.

I think he'd also failed to grasp that the USA and the British had the technology and logistics to do it, that it was actually possible to supply a city from the air.

(funky music) (indistinct announcement) (narrator) Radio broadcaster RIAS Berlin supplied moral support, keeping spirits up with American swing.

The Allied pilots became popular heroes, dropping chocolate and other sweets from their "candy bombers".

♪ In the almost 11 months of the blockade, West Berlin underwent a change.

And after the period of shortages, prosperity again grew apace.

That triggered anxiety in the East.

♪ (Frederick) The blockade of Berlin was another example of how Berlin was always going to be a thorn in the side of the Russians because it was a Western presence, it was a shop window for some kind of Western political and economic success.

(dark music) (narrator) In 1952, the living standard of East Germans was lower than it had been in 1947.

The privations led to discontent.

In June 1953, the people in the GDR had finally had enough of repression, scarcity, and patronizing government directives.

Party banners were torn down, workers went on strike, and the call for free elections became louder.

Shots were fired, tanks rolled.

The uprising came to a bloody end on the afternoon of June 17th.

(exploding, shouting) (somber music) ♪ Over the 12 months that followed, 400,000 people fled to the West, more than ever before.

In 1953, the GDR experienced the largest loss of population to date in its short history.

Ulbricht had an advantage, he could always point to the window display that was West Germany.

He could say, "See how my people have to suffer, and just look at how they're living in the West."

(moody music) (narrator) Nikita Khrushchev, the new man at the top in the Soviet Union, knew that East German leader Ulbricht was desperate to solve the West Berlin problem.

On November 27th, 1958, Khrushchev issued what would become known as the Berlin Ultimatum.

Within the next six months, the West was to enter into a peace treaty with both German states, and Berlin was to become a free city.

(cheering) That would have ultimately meant that the Western Allies would have had to pull out of Berlin, leaving West Berlin basically an island surrounded by the GDR, unprotected.

And it could then also be incorporated, bit by bit.

(clicking) (dark music) (narrator) But the West stood its ground and the numbers of those fleeing the GDR continued to rise.

In November 1960, Walter Ulbricht went to Moscow to appeal for a relaunch of the Berlin Ultimatum.

He had not forgotten Khrushchev's threat to sign a peace treaty with the GDR alone if the West refused to cooperate.

And Ulbricht also proposed building a wall to divide the city.

(soft piano music) Ulbricht had been requesting something like the Wall for a long time.

Khrushchev definitely saw Berlin as the West's weak point.

He put it quite crudely, in fact, in the peasant way he had, that it was like the balls of the West and whenever you want to make them squeak, you just squeeze them.

(narrator) In early 1961, the USA could still not fathom that a country would simply wall in its own citizens.

In January, when 43-year-old John F. Kennedy was elected President of the United States, both sides still believed a solution could be negotiated.

Khrushchev hoped that Kennedy could be convinced to give up all claims to West Berlin.

(soft music) ♪ (Matthias) He did not actually view Kennedy as an opponent.

Basically, Khrushchev was no intellectual.

He came from a farming family and was, to put it kindly, a very down-to-earth fellow who could be quite crude, but was also well aware of the position he held.

He perceived himself as a died-in-the-wool political animal.

♪ (narrator) Nikita Khrushchev felt superior to the West.

The Kremlin chief saw his Berlin Ultimatum as a demonstration of Soviet strength.

And the USSR did have legitimate grounds for pride.

Their rocket science was, in fact, superior to that of the West.

Khrushchev crowed that his country could churn out long-range missiles like sausages on an assembly line.

♪ Then, on April 12th, 1961, Russian Cosmonaut Yuri Gagarin became the first man in outer space, orbiting the Earth in 108 minutes.

It was the dawn of a new age, and a painful defeat for the USA.

♪ (whooshing) Writer Brigitte Reimann used red pen for her journal entry about the Soviet manned space flight.

The event strengthened her faith in the good side of socialism.

It hurt all the more that her beloved brother Lutz no longer shared her belief and appeared to now be gaining a foothold in the West.

(soft melancholy music) ♪ ("Ludwig Reimann") We've put the most difficult hurdles behind us and have no desire to ever go back now.

It's a good thing we left.

Sometimes the white-hot rage grips you, when you think about how they try to deceive the young people over there and take advantage of their ideals.

♪ ("Brigitte Reimann") At the moment I'm working on my story The Siblings.

The whole business with Lutz fleeing the GDR really got to me, and I'm trying to write it from my heart.

♪ I still have not forgiven Lutz for leaving.

♪ Yes, we did have a very close bond, but even a tie that binds will break at some point, and she never did forgive me.

I then became the family traitor.

Yes, really.

That word was actually used.

♪ (clicking) ♪ (narrator) In June 1961, tensions around the Berlin question were still running just as high.

At a summit meeting in Vienna, Khrushchev wanted to find out if Kennedy would risk going to war over Berlin.

Khrushchev feared that the West was just playing for time and waiting for the inevitable economic collapse of the GDR.

He wanted to finally push the peace treaty through.

That would mean the withdrawal of the Western powers from Berlin.

Otherwise, Khrushchev threatened, he would settle the issue of access to Berlin with GDR leader Ulbricht alone.

♪ (Frederick) This was a defeat for the young, glamorous Kennedy against the superficially clownish, but actually extremely ruthless and determined and aggressive Khrushchev, and it did set the scene for the Berlin crisis.

♪ Khrushchev thinks, "I'm coming here as the Soviet heavyweight to take the stage and tell the Americans how we're going to do things here."

And Kennedy thinks, "What does this country bumpkin want from me?

I'm the leader of the free world and I'm here to tell you Russians we're not going to budge a centimeter."

So it is basically the collision of two worlds that don't understand each other.

(narrator) When Kennedy and Khrushchev took off from Vienna, the superpowers were once again at each other's throats.

(clicking) Ulbricht felt that his time was coming.

Only one day after the close of the Vienna summit he ordered reinforcements for the security forces in Berlin.

(ominous music) That pointed to a major operation in the making.

The Socialist Party chief held a press conference on the morning of June 15th to announce that the signing of a peace treaty was imminent.

♪ (speaking German) ♪ (speaking German) (dark music) ♪ (Ilko-Sascha) The famous press conference gave a strong indication that something was afoot, otherwise he wouldn't have said what he did.

And when you look at it, refugee numbers had shot way up, there were huge economic deficits, there was major unrest in the population.

When you put all that together, in the perception of the GDR leadership, it spelled the threat of another uprising.

(melancholy music) (narrator) In June 1961 alone, almost 20,000 people had registered at the Marienfelde Refugee Center in West Berlin.

The situation in East Germany had become increasingly desperate.

Highly qualified professionals, especially, were choosing to flee to the West.

In her book The Siblings, Brigitte Reimann accused her brother Lutz of having been part of the move to bleed the GDR dry.

♪ By taking flight, he had betrayed Socialism and his sister.

♪ ("Brigitte Reimann") Lutz will, of course, I'm afraid, react with malicious derision.

Perhaps when he receives the book together with my letter, the last bridge between us will collapse.

In not a single line did I ever forget that I'm his sister and that I still love him.

My God, is that true?

And I hope he will feel it.

♪ She had split me into two people, so to speak, a good one and an evil one.

The evil one with horrible character traits, of course, had left for the West.

He was the traitor.

And the good one had been convinced by the discussions and remained in the Socialist fold.

Yes, it's true.

I was not thrilled with the book.

♪ (narrator) On June 7th, the East German Ministry of State Security, the notorious Stasi, gave the order to ramp up troop presence on the ring road around West Berlin.

Members of the Worker's Combat Group, a paramilitary unit, were issued gear and put on standby.

Members of the group assumed that they were being prepared to respond to the fallout from the signing of a peace treaty with the Soviet Union.

(soft music) They were stationed on the peripheries of Berlin to await deployment.

But, first, they were ordered to stockpile building materials.

They had no idea what for.

♪ Many people in West Berlin had by that time brought their most important documents, diplomas and the like, to friends and family in West Germany, because they assumed that something similar to '48/'49 would happen, another Berlin Blockade.

♪ (narrator) Seven weeks after the failed Vienna summit meeting, President Kennedy spoke to the American people.

In a televised address from the Oval Office he clearly affirmed his support of West Berlin.

(announcer) From the White House in Washington DC, we bring you now an address by the President of the United States John F. Kennedy.

(John F. Kennedy) Berlin is not a part of East Germany, but a separate territory under the control of the Allied Powers.

Thus, our rights there are clear and deep-rooted.

But in addition to those rights, it is our commitment to sustain, and defend if need be, the opportunity for more than two million people to determine their own future and choose their own way of life.

I admire President Kennedy in many ways, but I don't think that speech was particularly convincing to the audience.

If his audience was the American people, I think it probably was quite successful.

But if his audience was people sitting in a room in the Kremlin, I don't think so.

(somber music) As we see, it didn't stop them doing anything that they wanted to do.

(narrator) Kennedy's message was heard loud and clear in Moscow.

The Americans wanted to retain their stake in West Berlin, but as long as their physical access was not endangered, they would not prevent a wall from going up.

Khrushchev now had a free hand.

He had long pondered how to go about surgically dividing a major metropolis like Berlin in two.

Khrushchev was now convinced that only a wall could save the German Democratic Republic.

♪ (Frederick) Khrushchev spent days, apparently, early that summer, at his villa in the Crimea looking over maps of Berlin and talking to military experts and so on, and finally said, "Well, okay, it sounds a bit crazy, but I'll--we'll-- if Ulbricht thinks he can do it, let's see."

♪ (Matthias) On the very evening that Kennedy made his famous address in Washington, where everyone thought, "Oh, now Khrushchev will get cold feet," he made that call and said, "You have to build the wall."

On the next morning, the chief of staff of the group and his GDR comrades or representatives had already gathered to consult on how exactly to close off the border and then determined that it all had to be done on August 13th.

(clicking) (narrator) The noose was tightening.

On August 2nd, the East German police launched a campaign against the cross-border commuters.

The chicanery included increased passport controls at border railway stations, with frequent confiscation of ID cards, and the arrest of commuters on cross-border trains.

♪ (dramatic music) ("Brigitte Reimann") Yesterday evening was dreadful.

The Berlin crisis intensifies; a law against the cross-border commuters has been passed, the Western powers are in consultation; Strauss is calling for nuclear weapons and special powers to deploy them.

I was physically ill. We're teetering, still for years now, on the brink of war.

(clicking) (fanfare music) ♪ (dark music) (narrator) Two days after the summit meeting of the Warsaw Pact states, where the decision had been made to close the borders of the Western sectors, Nikita Khrushchev announced in a radio address his intention of beefing up military forces on the western border of the Soviet Union.

Unpleasant surprises should be avoided at all costs.

The West had now been forewarned.

♪ If Soviet troops as well as strategic military forces within the Soviet Union hadn't been put on combat alert, the Americans wouldn't have taken it so seriously.

(clicking) ♪ (narrator) On the morning of August 11th, the People's Chamber, the GDR parliament, resolved to take action on "preparations for the signing of a peace treaty with the Soviet Union."

The first measure would be to close the ring road around Berlin to stem the flight of East Germans to the West.

But Ulbricht purposely expressed himself in vague terms, fearing unrest within his own ranks.

♪ (Hans) The People's Chamber convened on August 11th and decided that a new border regime was to be put in place.

No one spoke of a wall.

The phrasing was a new border regime had to be devised.

And I, too, raised my hand and agreed that that had to be done.

(narrator) That August, writer Hans Werner Richter was holed up in his hometown on the Baltic Sea coast.

He noted: ("Hans Werner Richter") It's been raining for weeks and the nights are cold.

There is very little to eat.

"Something's going to happen," says fisherman Kollow, whom I'm lodging with here.

"They're up to something."

For two days now, police units have been leaving here for Berlin.

They're pulling together everything they have.

(engine puttering) ♪ (narrator) The national military forces of the GDR were put on combat alert.

Units in the catchment area around Berlin were put on standby, in case the combat troops and border police got into trouble.

♪ (Ilko-Sascha) They hadn't been told what their mission actually was.

Many of them thought it was all part of an exercise, a maneuver.

But that's standard military procedure, really.

People are no longer in communication, there's no contact with the outside world so everything can be prepared without interference.

(clicking) ♪ (narrator) Saturday, August 12th, was not quite the warm summer day Walter Ulbricht had hoped for.

But most Berliners still went out to the countryside for the weekend as usual, to visit family and friends.

No suspicions should arise.

(chuckling, shouting) (guitar music) We wanted Sunday to be Sunday.

We didn't want to do anything that might cause unrest.

It was a beautiful sunny day for going swimming in the lakes.

That shouldn't be disturbed.

But not to Wannsee, obviously.

Wannsee was already blocked.

(narrator) Many Berliners had also gone to the Baltic Sea coast for the weekend.

They reported that something was clearly afoot.

("Hans Werner Richter") The weekend bathers are still agitated.

"Ulbricht is planning something.

He's going to close the gate to the West," they say, but they also appear to have strong faith in the Western powers.

Had Kennedy not promised to keep the passage to freedom open?

And Adenauer?

Many of them swear by Adenauer.

(splashing) ♪ (narrator) At 8:00 p.m., Socialist Party leader Ulbricht issued the order from Berlin to implement Aktion Rose, Operation Rose.

Then, he drove to his lakeside holiday home.

(dark music) (Hans) Ulbricht had called the chairmen of the bloc parties, who also had their representatives in the government, to come join him at Döllnsee.

Coffee was served, and afterwards he informed them that the operation was going ahead.

♪ (Frederick) But the interesting thing is, they were not allowed to leave until the operation was underway.

So he didn't even trust the members of his own state council to keep the secret.

♪ (narrator) The only man Walter Ulbricht really trusted was Erich Honecker.

The then 49-year-old was entrusted with organizing Operation Rose: erecting the Berlin Wall.

(Frederick) He was in a position where he was pretty much guaranteed to be Ulbricht's successor, but he also knew that if he failed, that was probably the end of his career.

(narrator) At 1:00 a.m., the closure of the border began.

Chief organizer Honecker was chauffeured from one section of the border to the next, boosting troop morale while reassuring himself.

A successful wall-building operation would show that he was up to the top job.

Overnight, the entire city was ruthlessly divided.

Before morning, 68 out of 81 border crossing points had been closed with barbed wire.

When the sun rose on Sunday, August 13th, 1961, the fist makeshift lockdown was almost complete.

(rumbling) (somber music) ("Hans Werner Richter") It's five in the morning.

A door opens and then slams shut.

A voice penetrates my sleep: "You have to get up, now."

Fisherman Kollow stands at my bedside.

"Ulbricht has closed the sector borders.

You have to leave.

This will mean war."

♪ (clicking) ♪ (narrator) Operation Rose went off without a hitch.

The morning after, Berliners awoke to find themselves stupefied with horror.

I went out with the baby buggy and thought, "What's going on here?"

And then I saw that soldiers-- they stood right where you're standing now, and I was here-- were busy putting up the barbed wire, but only this high.

I could easily have just gone over.

I say, "What's going on here?"

And they say, "Step back, step back."

♪ (narrator) For the barely 19-year-old Kati Székely, August 13th marked her first shooting day on the film And Your Love Too.

In the film role, she was to choose between two brothers.

One earns big money in West Berlin, the other is a soldier in the combat group in East Berlin.

♪ The film was written by history.

I can remember, it was on the 12th.

On August 12th, we crossed the bridge, the Warschauer Brücke with the film team and they stopped us.

We were no longer allowed over the Western side.

♪ (narrator) This scene wasn't in the screenplay.

It was devised and shot ad hoc.

Current events shaped the film and the actors improvised the new material.

♪ (soft music) (speaking German) ♪ (narrator) Early that morning, Konrad Adenauer's advisor, Heinrich Krone, had contacted the West German Chancellor.

Krone would later note: ("Heinrich Krone") The door must not be allowed to close.

If the West misplays its hand this hour, Moscow will have won the game on a point crucial for peace, before a negotiation has even begun.

I don't believe that people in the zone will remain calm.

The fight for Berlin has entered a very critical phase.

(somber music) (Frederick) On the one hand, Western intelligence failed.

On the other hand, the East Germans and the Russians can congratulate themselves on running a very successful secret operation, which the enemy didn't realize what was going on until it was too late.

(narrator) On the morning of August 13th, the mayor of West Berlin, Willy Brandt, rushed to the border.

He felt blindsided and helpless.

He registered no increased military presence in the West Berlin streets.

The Allies were holding back.

He appealed to the Western powers, "We have to defend ourselves or risk losing face in the eyes of the entire world."

One of the cameramen who documented the closing of the border was Dieter Hoffmann.

On August 15th, he shot one of the most dramatic scenes of those fraught days.

(dark music) (Dieter) We came up to the Bernauer Strasse and there we saw a little cluster of people gathered on the other side.

And we thought, "What's going on here," and they said, "Well, he could make a getaway."

♪ You could tell he was struggling with something inside.

I wondered if he'd make a run for it or not.

And then I filmed him again, with his cigarette, as he turned to face the other side of the street where two men were still on patrol.

♪ They saw my camera and turned their backs to me and I panned back again.

At that moment I see him suddenly take a running start and he sprints right at me, jumps over the barbed wire, and as he's jumping, he throws his Kalashnikov or whatever, his machine gun, away, runs right past me to a police van, jumps in and just drives off.

♪ I was utterly dazed at the time.

I was unsure.

Did I have the right aperture?

Did I check the focus?

Did I just dream all that or was that reality, what I've just seen?

♪ (narrator) Border patrolman Conrad Schumann was an exception.

Most of his comrades dutifully guarded the makeshift blockade; no one tore the barbed wire down.

In the weeks to come, a stone barrier would be erected.

East Germany was walling itself in.

(shouting) ♪ ("Brigitte Reimann") Yes, of course, the big bad Bolsheviks!

By the way, we didn't cry over the new measure, which was actually long overdue.

Why shouldn't we bare our teeth too for a change?

(singing in foreign language) ♪ My sister actually expressed in writing that she had been glad about the building of the Wall.

I found that extremely offensive... ♪ ...which resulted in quite a fierce correspondence between us, because that was just beyond the pale.

(narrator) Many tried to flee at the last moment.

In the Bernauer Strasse, people jumped out of the back windows of their flats.

The sidewalk below was in the West.

Pictures like these shocked not only Ludwig Reimann.

(shouting) ("Ludwig Reimann") In Berlin they're putting up barbed wire, building multi-rowed concrete walls, turning Berlin into an army camp, swaggering with their weapons and threatening violence.

When I think of all that while reading your letter, I just don't want to believe it, that you're spewing out so much crap.

(shouting) (narrator) At this point, there were still cracks in the Wall, still chances to escape to the West.

But with every passing hour, the Wall took on the more permanent aspect of a bulwark that both stabilized and unmasked the GDR.

West Berliners were aware of this as well.

("Heinrich Krone") It is becoming increasingly clear that the Americans are not going to react.

The zone and also East Berlin offer them no incentive to intervene.

The population of Berlin is full of rage and bitterness towards the West, which is doing nothing.

Berlin feels abandoned.

(narrator) Two weeks after the border closure, Chancellor Adenauer finally visited West Berlin.

The 85-year-old got a cool reception from West Berliners and a cynical welcome from the East.

(speaking German) ♪ (narrator) Adenauer reacted to the dig with stoicism, demanded neither the opening of the border, nor did he wish to negotiate.

♪ Afterwards, there was a great outcry because, as the Bild tabloid headline read: "The West does nothing."

It couldn't do anything either because they knew the Soviet forces were there in the background, and anything we might do now could lead to nuclear war.

And that was a risk they didn't want to take.

They would only have taken that risk if the Allies' right to access had been denied.

(narrator) Precisely that occurred on October 22nd, 1961, ten weeks after the Wall had gone up.

A senior U.S. diplomat, on his way to the theater in East Berlin, was stopped at Checkpoint Charlie.

East German border guards demanded his identification papers.

The American refused to show the documents.

He refused to acknowledge East German border police and demanded to see a Soviet officer.

The situation escalated.

On October 27th, both sides let their tanks roll.

The Western Allies saw their documented access rights to the East zone endangered.

(Frederick) Nobody really wanted a war, but there was a real danger of war because America could not allow itself to be seen to be backing down in the face of this kind of threat against its rights in West Berlin.

The fact was, American prestige was involved and that was how we got to this point.

(narrator) On that day, Soviet and U.S. troops faced off as enemies at Checkpoint Charlie, ten on each side.

(squeaking) ♪ (engine puttering) ♪ But the even score was an illusion.

12,000 Western Allied soldiers were met with 350,000 Soviet troops.

The situation could hardly have been more asymmetrical.

(Frederick) It was a situation of mutual provocation, particularly provocation from the East, of course.

But it was mutual, too.

It was a place where they could play out this rivalry in a kind of...

It was almost like shadow boxing.

(narrator) The crisis lasted only a few hours.

Thereafter, Western diplomats produced their documents without resistance.

The Wall was accepted, and the presence of the Allies in the Western sector of Berlin was no longer called into question.

(moody music) (Matthias) Basically, they were all contented that the Wall had gone up.

Ulbricht had saved his country; the wave of emigration had been stopped.

Khrushchev had saved the GDR, had virtually cemented it to the rest of the Soviet Bloc, to keep it from falling apart, too.

The Americans had basically saved West Berlin.

And the fate of the GDR citizens was then a moot point.

That is, they had to be sacrificed on the altar of peace and freedom.

(narrator) The division of Germany had literally been cemented.

It would shape an entire era, and force Germans in East and West to go their separate ways.

♪ (bright music)