For most of the latter part of the 20th century, Berlin has stood as a symbol of the division between East and West, split by the infamous fortified wall erected to separate the socialist sector from the democratic district. When the Berlin Wall was pulled down in 1990 the city discovered that it suddenly had two of everything, most notably two very distinct societies separated both socially and economically. The past decade has seen Berlin embracing unification and rebuilding itself as a modern European capital. More than 100 streets have been reconnected, and signs of the Wall's existence have all but disappeared. Years of division are still reflected in the new city's architecture, however, with a modern city of skyscrapers, retail centres and urban developments in the West contrasting with most of the pre-War city that remains in the East. For nearly 30 years the Wall sealed off the imposing Brandenburg Gate from the West, but now traffic passes through it freely. Similarly Alexanderplatz, which was one of the main centres of 1920s Berlin, and later post-war East Germany, has once again become one of the city's focal centres. The site of the infamous Check Point Charlie with its threatening monitoring tower erected to ensure no one crossed over from East to West, is now a museum, and while the tower no longer stands, visitors can see the East Side Gallery, a surviving chunk of the real Wall, now decorated by local artists. Berlin is once again a vibrant centre for the arts, with many museums, galleries and theatres. At the Kulturforum visitors will find a number of impressive museums and concert venues from the spectacular Berliner Philharmonie concert hall to the complex's Picture Gallery, which houses a vast collection of European paintings from the 13th to 18th centuries. Berlin still boasts a fantastic nightlife, and while tastes have changed since the height of the cabaret halls of the 1920s and 30s, there is a vast array of venues catering to all tastes. Berlin's calendar is also packed with festivals and parties from the Christopher Street Day gay and lesbian parade in June to the massive Love Parade dance party in July and the Jazz Fest Berlin in November.