Santorini Caldera

The crescent of cliff-top villages -- Fira, Oia, Imerovigli -- perched on the rim of a volcano that exploded around 1627 BC and may have destroyed the Minoan civilization, creating the world's largest caldera still visible from space, is the most photographed landscape in Europe. The blue-domed churches and whitewashed cubic houses of Oia at sunset attract 10,000 visitors daily in peak season to a village of 1,500 residents, and the view across the caldera to the still-active Nea Kameni volcano is the defining image of the Greek islands.