One of Europe's most romantic cities, water capital Venice is built on more than 100 small islands in a lagoon in the Adriatic Sea. It has no roads, just canals – including the Grand Canal thoroughfare – lined with ornate Renaissance and Gothic palaces. The central square, Piazza San Marco, has famous landmark St. Mark’s Basilica, which is tiled with Byzantine mosaics, and the Campanile bell tower offering views of the city’s red roofs.