These ruins of a pre-Columbian cliff village are among the most beautiful and well preserved in New Mexico.

Under the right circumstances, this waterfall in Yosemite briefly turns a luminescent fiery orange.

This magical grotto is adorned with a complex pattern of native seashells, minerals, and fragments of colored glass.

This massive underground salt mine now holds a sci-fi theme park in its depths.

The Beaux-Arts aquarium boasts a vast collection of saltwater and freshwater fish on an island in the Detroit River.

Stuck in a bygone era, the oldest subterranean shopping street in Japan hides beneath the popular Asakusa district of Tokyo.

Ute tour guides have been sharing the ancient dwellings and rock art inside this large park with visitors for more than 40 years.

This abandoned island off the Venetian coast has been a radical monastery, a political prison, and a secret Nazi base.

Ruins of a Carnegie family mansion on Cumberland Island.

This Canadian island is a veritable garden of decay with countless abandoned structures dotting the landscape.

This foolish Victorian sea fort was converted to a deluxe hotel.

This post-war motel embodies a little-known, Miami-born architectural style.

The superstar of Cold War nuclear bunkers has been featured in countless films but is now barely operational.

This North African stone complex is considered to be the oldest astronomical observatory on Earth.

A historic jail preserves etchings from over a century of incarcerated people in a town with a rough and tumble past.

This gem of Moorish architecture is slowly disintegrating along the coast of this charming town.

For nearly 50 years this airplane that crashed during World War II remained missing in the remote Australian backcountry.

Founded by French colonists in 1919, this mountain resort has been transformed into one-of-a-kind theme park.

The Bulgarian royal family exclusively used this ornate, now-abandoned train station.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

In the mountains of West Virginia is this perfectly preserved Art Deco train station.

An ancient city exhumed from the depths of the ocean.

The oldest known metal-mining site in England dates back to the Bronze Age.

The alleged vampires after which these islets are named may have actually been plague victims.