The Inca ruins at Moray, an archaeological site in Peru, feature a massive bowl-like depression, with a series of concentric terraces that are split by multiple staircases and look like an ancient Greek amphitheater. The largest descends to a depth of approximately 150 meters and leads to a circular bottom so well drained that it never completely floods, no matter how plentiful the rain. Legend has it that if you enter but are not pure of heart, you turn into a small pile of stones.

