Disused penal colony features prisoner artwork, some sketched in human blood.

An artist's cute bronze subway sculptures belie his violent artistic past.

Rare karst landscape eroded from a flat seabed.

Sculpture garden of religious statues made it through Soviet rule.

A natural arch offers panoramic views of Yangshuo's karst hills.

The smallest country in the world.

Silent memorial, using bone conduction to take people back to the Dresden Bombing of 1945.

A 15th-century granary that played the role of futuristic slave quarters in the world of 'Star Wars.'

Gigantic natural towers in a Russian plateau.

This stunning, out-of-the-way Croatian monument commemorates a community's uprising against occupying fascist forces.

Stay in a room with a view... of the bottom of the ocean.

Gigantic unfinished stupa and the world's 2nd largest bell.

Houses are tucked between, on, and underneath giant boulders.

Mysterious standing stone formations looks like a petrified forest.

The remains of a sunken military ship wreck visible through clear water.

An Italian hillside ghost town.

Tubing through a cave lit with glowworms is a magical underground experience.

Natural time capsule containing an alien ecosystem.

Hundreds of caves once used to store grains and animal feed.

Founded as a refugee camp, now a popular tourist spot.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

One of the most spectacular canyons in the world.

Annual rush for a sacred desert lake's fish stock.

Hot springs monkey spa in the middle of Hell's Valley.