This whimsical castle of grottoes was the labor of love of a French postman, and one of the greatest achievements of outsider architecture.

The world's brightest bioluminescent bay.

Largest collection of mounted dinosaur specimens in the world.

A battle between nature and architecture in the Cambodian jungle.

Centuries-old bridges grown from tangled roots.

Furniture tries to escape an abandoned building in San Francisco.

The enigmatic and seldom visited ruins of a Mayan city-state.

Monasteries on rock pillars, once accessible only by frayed ropes.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

Treehouse motel and treehouse-building school.

France's most famous cemetery, with some of its most curious tombs.

This quirky curiosity shop takes its cues from the world's bazaars.

An Amsterdam street lined with antique shops each one dedicated to a different obscure collection.