Thera, Greece (#1)
Phera, a city built on the caldera rim of Santorini (also known as Thera), a volcanic island in the Aegean Sea, is often visited by cruise ships sailing the Eastern Mediterranean. The huge eruption and caldera collapse that provided Phera's perch occurred about 1600 BC, and may have been the germ of truth in the Atlantis legend.
Photo copyright R.W. Decker.