My family is originally from Germany, Eastern Europe and Russia. Most left Europe before World War II; some were not as fortunate. For more than 20 years, I have taught a college course on the Holocaust, and every year we watch the same gruesome, black-and-white films of war-torn Europe. I tell my students about my visits to the former death camps in Poland and my numerous trips to Berlin, the center of Nazi power in Europe. “How can you go there?” they always ask. “Well, the war ended 45 (or 50, or 55) years ago,” I would answer. This year I said, “… it was 65 years ago.”

They turn their 18-year-old faces toward me, eyes wide, not comprehending what they have just seen on the screen. They don’t understand how Berlin, that Berlin, could now be a dynamic capital of a European country, a place where people willingly go to spend dollars or earn euros, where there are more opera houses and museums than any city in the world. I tell them that Berlin hasn’t tried to hide its past from visitors, but uses its history to educate the world about tolerance, redemption and reunification.

I tell my students that Berlin has one of the most diverse urban populations in Europe, a city where Jews are now respected and important citizens, a place where media is free-spirited and independent, and where art and music flourish. It is a place where young people have no memory of war or walls. They kiss and laugh and enjoy themselves on weekends, just as my students do.

I tell them that after high school I worked for a year to pay for my first trip to Europe, in 1964, a four-month adventure that included driving a tiny Citroën 2-cv from Paris to Berlin through the barbed-wire-protected pastureland of East Germany, where stopping along the road was strictly verboten. It was a thrilling adventure to be questioned by border guards at Checkpoint Charlie when obtaining the necessary day-pass to drive through the three-year-old Berlin Wall.

I tell the class about Ulrike, my first real girlfriend, a West Berliner a few years older than I. She looked like Brigitte Bardot (the actress was only 30 at the time; most of my students have never heard of her), spoke English fairly well and told me hesitantly that her father had been a soldier in the German Army during World War II. Even that didn’t matter. She was exotic and blonde and took me to beer gardens, where we sat for hours drinking beer, listening to music, casually leaning our shoulders into each other while the summer sun drained from the sky. Above us, as the night air turned cool, strings of white lights swayed in the branches of the linden trees.

Ulrike moved on to university, got married, had children. We lost touch, but I returned to the city several times during the 1970s and ’80s. In West Berlin, I would stand atop wooden viewing stands near the wall and stare into the gritty cityscape of East Berlin, watching East German border guards, bundled in gray military coats, stare back at me. Forlorn East Berlin apartment buildings stood a few feet from the wall, their west-facing windows bricked up to prevent escapes. The spirit and energy of the West Berliners was amazing but always tempered by the presence of the wall, of attempted escapes gone wrong. Sometimes, on winter days, when a cold pewter sky covered the city and dirty snow lined the streets, I couldn’t wait to leave.

When I return to Berlin these days, now 20 years after reunification, I am older than most of the Berliners I meet. Many East Germans, old and young, moved to other German or European cities as soon as the wall fell, happy to be far away from their former homes in the GDR. In the reverse direction came seekers, young, ambitious, creative West Germans and other Europeans, flocking to a reunified Berlin for the cheap rents in former eastern neighborhoods, to eat in the trendy, new restaurants built within former communist government buildings or to exhibit art in one of the eclectic galleries that now fill the narrow streets of Mitte, Prenzlauer Berg and Friedrichshain.

Famous architects like Eisenman, Foster, Libeskind, Koolhaas and Chipperfield came to design new museums, embassies and the iconic Holocaust Memorial in the middle of the city. Developers put up new office parks, shopping centers and clothing boutiques. Everyone came to experience the heady spirit that filled (and still does) the city’s jazz clubs and bookstores, the restored Potsdamer Platz and the glass-enclosed Reichstag dome. University sociologists in Berlin, whose urban laboratory suddenly doubled in size, were stunned to learn that many East Berliners who stayed to witness the changes were now nostalgic for their more simplistic communist lifestyle. But with more art galleries, cabarets and cafés than factories and corporate headquarters, Berlin looks richer than it is. The city’s social democrat mayor, Klaus Wowereit, a popular gay politician, calls Berlin “poor but sexy.”

Berlin has become a very cool, of-the-moment capital city, yet still unpretentious and laid back as if, after a century of misfortune, it is not quite sure it can now relax. During a recent visit I spent several hours in the Clärchens Ballhaus, a 90-year-old, high-ceilinged dance hall in a three-story Mitte building. Unlike many other former East Berlin buildings, the Ballhaus has not been renovated. It is 1920s Weimar Republic décor and is always rocking with a great DJ. I go there to dance, something I never do anywhere else. There is food and a bar, loud music and friendly vibes. There is no velvet rope outside, and no one cares what you wear.

Berlin is a European city without a hint of stuffiness. Sit on the patio outside the minimalist restaurant, Schneeweiss, and you can start a conversation with anyone. Almost all Berliners speak English, are accessible, introspective, quick to laugh and in Berlin for the same reason you are: to experience urban life at its best, not in any hedonistic way, but intellectually, with food, good books, great music and an appreciation of the city’s sensuality. They live with the same baggage we all do, perhaps more so, but Berlin itself seems to give them sustenance.