A few stone foundations and an old graveyard are all that is left of this once thriving settlement in the wilds of Connecticut.

All that remains of the Whittall mansion are the ruins of the formal garden and its pergola, dedicated to the late Matthew J. Whittall by his widow.

America's oldest archaeological site or a muddled case of wishful thinking.

An 80-year-old house built out of newspapers.

Friction between grains of sand cause a curious "singing" sound.

This Gothic castle was inspired by Erik the Red's Viking residence at Brattahlid in Greenland.

The macabre graffiti spectacle in a quarry in a Massachusetts forest reservation.

This headstone-like marker inscribed with three words has been an utter mystery for over a century.

Possible relics of the ancient Roman city are hidden in this restaurant's façade.

Buildings that dynamite couldn't bring down were abandoned because of bathroom issues.

A coastal rock outcrop with mysterious inscriptions variously attributed to Native Americans, Portuguese, Phoenicians, Norse, and more.

A red brick monolith is all that remains of New England’s first commercial brickyard.

The city of Halifax still bears the scars of the largest explosion prior to the atomic bomb.

This enormous "cloth of the conquest" depicts the Norman invasion of England in mind-blowing detail.

This modern French ossuary contains the jumbled bones of 130,000 WWI soldiers.

Site of one of World War I's most horrific scenes.

The ruins of a 2,000-year-old Roman fishing village perched on one of the best beaches in Spain.

Along the most northwestern point in Africa is an ancient cave surrounded by legends.

This triumphal arch is the only fully standing structure that remains from Roman-era Oea.

Magnificent Roman ruins lie vulnerable to destruction on the edge of the Mediterranean.

A minotaur, a labyrinth, and a dubious restoration pull in visitors from around the world.

Cretean quarry suggests real-life site for ancient Greek myth of the man-eating Minotaur in his labyrinth.

The oldest olive tree in Greece has been bearing fruit for at least 2,000 years.

This column celebrates Rome's victory over the Goths, and may be the oldest Roman monument in Istanbul.