A collision of human error and natural geothermal pressure created this rainbow-colored geologic wonder.

An eerie, derelict amusement park in Berlin.

Occupied for six centuries by Franciscan Order nuns, this monastery is an amazing ode to Catalán Gothic architecture.

No one's quite sure why there's a metal megaphone bolted on two rocks in the middle of the Mojave Desert.

This hulking behemoth is actually five interconnected towers built in the 1960s.

Heralded as the world's first theater, these ruins are often overlooked as they reside in the shadows of the Acropolis.

Blue-green pools and smooth stones comprise one of Spain’s most idyllic hidden wonders.

The United States's largest hand-dug well is topped with a state-of-the-art museum.

A ruined Maya city that suffered a years-long case of mistaken identity.

A modern zoetrope on the New York City subway.

An abandoned set from the 1980 film "Popeye," claimed and repurposed as a theme park by creative locals.

L. Frank Baum wrote part of the "Wizard of Oz" series in this wooden Victorian beach resort.

This "cursed house" features secret rooms, hidden vaults, and dark escape tunnels.

A unique collection of diving equipment spanning antiquity to the present day.

Ancient Egyptian relief, claimed to depict an electrical light.

One of the most well-preserved temples of ancient Egypt.

Known as the Sistine Chapel of Egypt, this tomb houses some of the most well-preserved paintings in Egypt.

Preserved Inca city and site of the last Inca stronghold against the Spanish conquistadors.

Sited in an Inner Mongolian desert are the remnants of an important trade stop along the Silk Road.

Extraordinary sculpture garden created by an eccentric English poet.

A barbarous band of serpents guard the bases of these Aztec temples.