First, a condensed history of the Berlin Wall to provide some background knowledge (huge thanks to my host dad and the internet for helping me with my research)
At the end of World War II, both Germany and Berlin were divided into four zones - each was occupied by either France, Great Britain, the United States, or the Soviet Union. The plan had originally been that Germany would one day be reunified, but by 1949 there was a lot of tension between the occupying countries, resulting in the Allied Powers (US, France, Great Britain) combining to form the democratic West Germany (Federal Republic of Germany), while the Soviet Union formed the communistic East Germany (the German Democratic Republic). The same division between democratic West and communistic East occurred in Berlin. But since Berlin was located in Eastern Germany, West Berlin was like a little island of democracy, completely surrounded by a sea of communism.
Soon after the war, the Allied powers supported West Germany in creating a capitalistic society and revitalizing their economy, but meanwhile in the East, personal freedoms were being limited and the economy was dragging. By the late 1950s, many Germans were tired of living in the repressive East and wanted to move to West Germany. By 1961, 2.5 million East Germans (many of whom were young, trained professionals) had fled, which was obviously bad news for the East, as much of their working force was disappearing, making the economic problems even worse. Many of these refugees were going to West Berlin, and then staying in warehouses before flying to West Germany. The easy solution for East Germany would be to take over the West Berlin. This had been attempted multiple times, but the Allied Powers were determined to maintain democracy in West Berlin. Desperate to keep its citizens, East Germany secretly decided to build a wall in Berlin to prevent anyone from crossing the border. Their "official" reason was that they wanted to keep West Berliners out, but it was obvious that their real reason was they warned to keep the East Germans in.
In the night of August 12/13, 1961, crews of soldiers and construction workers tore up the streets, dug up holes to install concrete posts, and strung barbed wire all across the border between East and West Berlin. Any telephone wires between the two sides were cut.
When Berliners woke up the next morning, they were surprised to find this new border. Whichever side of the wall one went to sleep on during the night of August 12, was the side where they would be stuck in for decades.
The Berlin Wall stretched over one hundred miles, completely cutting West Berlin off from the rest of East Germany. And although it began as just barbed wire, that was soon replaced with large blocks and later concrete slabs (12 feet high and 4 feet wide, with smooth pipes along the top to prevent anyone from climbing over). By the 1980s, there was a 300 foot No-Man's-Land, an additional inner wall, patrolling soldiers with orders to immediately shoot escapees, a raked ground to show footprints, vicious dogs, anti-vehicle trenches, electric fences, massive light systems, watchtowers, bunkers, and minefields. There were small openings, called check-points, for the infrequent use of officials or others with special permission to cross the border (the most famous of which is Checkpoint Charlie - the main access point for Allied personnel and Westerners to cross the border).
In September 1989, after the wall had been standing for 28 years, a Peaceful Revolution occurred in East Berlin. Communism was faltering in Poland, Hungary, and Czechoslovakia,
and many young people in East Berlin were dissatisfied with the state-imposed constraints, holding large demonstrations and shouting, "Wir wollen raus!" (We want out!).
On November 9th, 1989, Egon Krenz (the leader of East Germany), finally decided to allow people to exit directly through crossing points between East and West Germany. This drastic change would take effect the next day, giving time to inform all of the border guards. The job of announcing this to the public was given to Gunter Schabowski (the party boss of East Berlin), despite the fact he had not been present for the decision making and did not know all of the details or how to handle the information. He was simply given a note, which he read out during the press conference. A reporter then asked him when these changes would take place, to which Schabowski guessed, "As far as I know, effective immediately, without delay".
No East Berlin authorities wanted to be responsible for giving instructions for the wall's soldiers to use lethal force, but the guards were quickly becoming outnumbered by swarms of East Germans demanding to be let through "as Schabowski said we can". Finally, at 10:45pm, the checkpoints were officially opened. The West-Berliners welcomed back their neighbors, friends, and family - there were huge celebrations for the rest of the night over everyone's new freedom, ultimately leading to the reunification of Germany a year later.
To set the scene:
Two days before the anniversary, 8000 white illuminated balloons were hung in the streets of Berlin, forming fifteen kilometers (nine miles) of the former wall's path. And according to a nifty little brochure I got, the balloons were also there to represent the candles which were a non-violence symbol during the Peaceful Revolution in 1989. Each of the eight thousand balloons on the path had a patron, who had written a personal message that would fly up with their balloon.
Even though the balloons wouldn't be lifting off into the air until 7pm, my host family and I went in the afternoon to the central Berlin area just so we could see everything. And let me tell you - it was incredible. The balloons were so big, and they shined spectacularly in the dark. We walked along part of the path and took a lot of photos, but clearly we weren't the only ones with the idea to arrive early - all forms of public transportation were packed, and it was difficult to maneuver in the streets due to the sheer masses of people wanting to witness the celebration.
Around 6pm we walked (or rather pushed/squeezed, as the streets were all jam packed) over to Potsdamer Platz (near the Brandenburg Gate and Reichstag). Once a busy city center, Potsdamer Platz became completely desolate waste-land after it was split in half by the Wall, and then in 1989 it was one of the first locations where the Wall was dismantled and crossed. After the fall of the Wall, Berlin recognized the potential this square had to once again become a city center in Berlin, and so in 1991 the Berlin Senate held a worldwide competition to decide the fate of the square's new architecture and design. The result, which can be seen today, is pretty awesome - this square has been completely transformed into one of the hottest places in Berlin.
Around 7:20pm, after some delay, the first balloon floated up into the dark sky in front of the Brandenburg Gate, as Beethoven's Symphony Number 9 was played by the Berlin State Orchestra. From there, the rest of balloons were cut by the patrons one at a time. This was a surprise to a lot of people (We had thought every balloon would fly up simultaneously. However, staggering them actually turned out to be a great idea - if they had all gone up at once, I think the public transportation might have exploded because everyone would have left at exactly the same time).
Then, at 7:27pm, the balloons right near where my host family and I were standing started to rise into the air (see video below). People were shouting, cheering, and just celebrating - it was a moment I will definitely remember for the rest of my life.
To celebrate the event, Germany's chancellor Angela Merkel made a speech saying, "Träume können wahr werden. Nichts muss so bleiben wie es ist." I was pretty excited not only because it's a beautiful line, but also because I understood what it meant! "Dreams can come true. Nothing must stay how it is."