The skull of the patron saint of lovers lies in the Basilica di Santa Maria in Cosmedin—maybe.

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

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

A graveyard for early settlers, sometimes called Old Pioneer Cemetery, hidden in the woods on a hillside.

An abandoned 19th-century hospital now swirling in ghost stories.

A nearly abandoned 19th-century town on the Palouse.

The century-old remains of an abandoned farm town in eastern Washington.

This Cold War missile launch site has been abandoned for 40 years.

The site of the Wellington avalanche, one of the America's worst railroad disasters.

From overly ambitious (and eventually abandoned) atomic dream to bustling office park.

This hotel has hardly changed in over a century, like a time capsule of old Oregon.

At the base of Steens Mountain resides an otherworldly desert.

Shakespeare has been brought to life in this open air theater for the better part of a century.

This historic steamboat is scuttled just a few hundred feet from where it was built over a hundred years ago.

This natural marble cave is one of only five national monuments in Oregon.

The short-lived railroad town in central Oregon has been abandoned since the 1930s.

While it is not equipped to peer into outer space this observatory looks like it was built on the moon.

A tourist attraction founded around a slumping cabin.

This strange hill on Old Fort Road where gravity works in reverse has been fascinating locals for years.

The trunks of 3,000 year-old trees lurk beneath the surface of this crystal clear lake in Oregon.

This former mining hub holds a surprising abundance of undisturbed relics from the Old West.

A short hike into the mountainside forest reveals a decaying 1890s town.

The longest continuous lava tube in the continental U.S. offers 2.5 miles of dark explorations for the adventurous.

A volcanic fissure over two miles long and up to 70 feet deep.