An American flag was erected for every day that passed during the Iranian Hostage Crisis.

Sail through this subterranean show cave that is home to a legend that would go on to name nearly everything around it.

Few other hotels can rival the grandeur of the Castle in the Rockies.

A mysterious taxidermy man-beast of the seven seas.

The frozen bubbles that form on the icy surface of this Canadian lake contain enough methane to create a small explosion.

Life in this isolated, hilltop lighthouse was lonely, but it sure was lovely.

Centuries of crashing waves carved out this small hole in the rock, which lights up at certain parts of the year.

Once the "Eighth Wonder of the World," this iron railroad bridge was decimated by a tornado.

Ruins of a historic medical facility sits eerily by the water.

New London, Connecticut still holds a grudge against its hometown son who turned traitor and burned the city.

The closest thing to Mars on Earth.

This massive subterranean fissure is known as the "underground Grand Canyon."

Crossing this suspension bridge feels like walking through the sky, a fitting tribute to the head of the Apollo program.

A climbing route in the mountains of Italy’s Dolomites, built for soldiers during World War I.

Walk inside a half mile long crevice right outside the town of Garmisch Partenkirchen.

Crumbling ruins of the thermal baths that once attracted royals and aristocrats from throughout Europe.

A line of abandoned, alien-like fortresses dot the mountains of North Italy.

An abandoned amusement park hints at the twisted history of the Newfoundland Railway.

This giant squid sculpture sits near the spot where a real-life specimen was captured in the late 19th-century.

Hundreds of enormous icebergs drift through this waterway every year.

The fairy tale castle of the "fairy-tale king."

German and American troops joined forces to defend this fortress during the strangest battle of World War II.

The last fully functional fortress of Germany's World War II Atlantikwall.

Monuments don't get much more metal than these three giant viking swords planted in a Nordic hill.