Harry's Bar is a bar and restaurant near St Mark's in Venice (in the picture). Harry's Bar has long been frequented by famous people, and it was a favourite of Ernest Hemingway. Other notable customers have included Italian conductor Arturo Toscanini, inventor Guglielmo Marconi, Charlie Chaplin, Alfred Hitchcock, Richard Halliburton, Truman Capote, Orson Welles, Baron Philippe de Rothschild, Princess Aspasia of Greece, Aristotle Onassis, Barbara Hutton, Peggy Guggenheim, and Woody Allen.

Caffè Florian and Caffè Quadri are round the corner from Harry's in St Mark's Square, but they are, of course, cafes, not bars. You need a boat ride to get to the Cipriani -- it's a hotel (not a bar) across the water on the island of Giudecca.

More Info: en.wikipedia.org