Located on the eastern coast of the Salento Peninsula, the Strait of Otranto—from which the city takes its name—connects the Adriatic Sea with the Ionian Sea and separates Italy from Albania. It is also the easternmost point of mainland Italy. The city was once ruled by the Byzantine Empire, and works of art still adorn the walls of the Church of San Pietro, along with a stunning mosaic floor in the cathedral, which was inaugurated in the 11th century. From the large fortress, Castello Aragonese, one can gaze out over the sea and its crystal-clear turquoise waters.