On the Oregon coast there is a natural hole that seems to be draining the sea.

What was to be the world's most secure Cold War document vault ended up as just a few shallow caves.

This WWII-era military installation once held an entire city within its walls - now, its walls are falling down.

This small city where almost everyone lives in the same building can only be reached via North America's longest tunnel.

Once described as the "Eagle's Nest," this ruined ancient city rests on a remote mountaintop.

This public art piece proves that in Portland even reporting the weather is a thing of whimsy.

The seamy, underground secrets of Portland's criminal past.

Beyond being incredibly fun, not much can be said about the Hole with certitude.

This abandoned fort is said to be the most haunted place in India, so much so that entry is prohibited after sunset.

An abandoned saucer-shaped monument in the Bulgarian mountains.

A pair of trees near a Hong Kong shrine are said to grant wishes, but only the ones they hold on to.

The remains of a town so thoroughly destroyed by French forces that the citizens simply left.

This Italian foot path winds through the mountains via 52 individual tunnels.

This series of underground chambers contains Europe's largest subterranean lake that is slowly drained each day.

A metal tree emits eerie, melodic notes on top of Lancashire's Crown Point.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

An 18th century monument regularly tagged with unsettling graffiti referencing a 1940s unsolved murder.

One man has carved a number of natural New Mexico caves into psychedelic sandstone temples.

A bizarre house filled with an astounding array of collections.

The giant figure on the back of this turtle-shaped temple actually hides a memorial pendulum.

The atmospheric road was never meant to be so creepy.

A unique waterfall that some believe attracts the fairfolk.

Abandoned medieval hill town.

This black church sits alone among a field of lava rock.