What is the area of Berlin?
Berlin
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Unter den Linden is a tree-lined east–west avenue from the Brandenburg Gate to the site of the former Berliner Stadtschloss, and was once Berlin's premier promenade. Many Classical buildings line the street and part of Humboldt University is located there. Friedrichstraße was Berlin's legendary street during the Golden Twenties. It combines 20th-century traditions with the modern architecture of today's Berlin.