The remains of a magnificent medieval fortress that was the capital of a vast empire.

The largest madrasa in Morocco once housed more than 900 students within its exquisite walls.

An eerie, derelict amusement park in Berlin.

Bring your own cardboard to the slippery slopes of concrete hidden in a neighborhood park.

During prohibition, corrupt city officials ran drinking dens under the streets of Downtown Los Angeles.

A ghost town that held steady longer than most, but finally gave up the ghost.

This ghost town was once a cult-like religious utopian settlement.

Settled by the Church of Jesus Christ of Latter-day Saints in 1859, this abandoned frontier town has appeared in several films.

A well-preserved Ancestral Puebloan ruin tucked beneath a desert cliff.

One man has installed bathtubs into the Utah desert floor to harness the powers of a natural hot spring.

Here, at the "world's longest art gallery," you'll find forty miles of ancient petroglyphs and pictographs.