A night out at Clärchen's Ballhaus (Little Clara's Ballroom) is like a trip back in time. Opened in 1913, the club is an impressive sight on Mitte's now-upscale Auguststrasse. On summer nights, lines often stretch out the door, while the front courtyard comes alive with patrons dining alfresco on brick-oven pizzas. The main ballroom features a different style of music every night and there are often dance lessons before the party starts. One of the best things about this place, though, is the variety of people of different ages, nationalities, and social backgrounds mix. The upstairs Spiegelsaal ("mirror hall") has intimate, salon-type concerts on Sunday.