Venice, the capital of the Veneto region of northern Italy, encompasses more than 100 small islands in a lagoon of the Adriatic Sea. It has no roads, but only canals, including the Grand Canal thoroughfare, lined with Renaissance and Gothic palaces. In the central square of San Marco, is the Basilica of San Marco, which has a Byzantine mosaic floor, and the Campanile bell tower overlooking the red roofs of the city.