Museum on French naval history, with magnificent figureheads, a historic diving suit, and a boat used by Napoleon.

There is only one place in the world where the corners of four nations come together.

A hidden piece of Altoona's railroad history in a long-forgotten abandoned town.

The ruined remains of a coal mining ghost town are hidden within the woods.

A magnificent mansion hides a delightful collection of historic timepieces.

A hidden three-foot-wide house separates these two regal churches.

Seven people are buried in the middle of what's now a movie theater parking lot.

The only statue of its kind to commemorate Washington's beginnings as an officer of the British Colonial Militia.

An intriguing three-sided folly is a testament to one man's devotion to Catholicism and the number three.

A cavernous three-story, 43,800-square-foot basement that was forgotten about for 60 years.

The only surviving piece of a submarine said to be the most decorated vessel in U.S. history.

The ruins of an 11th-century Norman castle with a rare, perfectly circular shape.

A long spiraling walkway winds through the woods, and around a copper beech tree at the center.

Now abandoned, the world's first torpedo factory is crumbling into the sea.

This tiny Minnesota city tried to secede from the Union as a last-ditch effort to fix its crumbling water system.

In an odd geographic anomaly this city borders two different states on opposite sides of town.

Scattered ruins and a tiny cemetery are all that remain of a failed attempt to colonize the inhospitable Desolate Islands.

This two-towered gateway is all that remains of the unluckiest pier in the world.

Some of the world's largest letters are carved into the limestone bedrock of the Nullarbor Plain.

Purdue students would lean over this iron fence to skirt campus rules against smoking and courting.

These old doors are covered in the signatures of Rehoboth Beach artists dating back to the 1930s.

World War II-era bunkers are hidden under the beaches of this picturesque park, which is still scattered with wartime watchtowers.

The historic home still shows the scars from a little run-in with the British in 1813.

What began as an art installation is now the private drinkhaüs for a brewery's employees.