One of the city’s best-loved “champagne bars” since 1929, El Xampanyet knows that no bar ever went broke by selling inexpensive drinks. By day it keeps a low profile just across from the Museu Picasso; the corrugated steel door does not roll up until the museum closes. In minutes, Xampanyet is jammed, as drinkers assemble next to wine barrels, marble-topped tables, or the long zinc bar as if someone were about to start shooting a party commercial. Tapas are simple and salty (olives, ham, croquettes), and the house cava (white or pink) is a great deal.