This ancient Irish religious site is covered in ancient carvings, many of which have barely aged.

A church that bred legends, and served as an inspiration for the Da Vinci Code.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

A collection of haunted objects and macabre oddities under one roof.

Mysterious meeting place for UFO hunters near Area 51.

An eatery for UFO seekers on the Extraterrestrial Highway.

This beloved roadside attraction welcomes visitors with his signature neon smile.

In the middle of a remote desert town is a surprisingly opulent hotel.

There's nothing creepier than a cemetery next to a clown motel.

Oh, just a motel on the edge of the desert decorated with thousands of clowns conveniently located next to an abandoned graveyard.

A popular tourist cave with a dark past.

This haunting tombstone comes complete with a heartbreaking story of love and loss.

More than a century after her death, Little Gracie Watson remains one of Savannah's most often-visited residents.

An early-19th-century hotel with a past that is steeped in the Civil War.

An eerie smiling woman looms above the granite tombstones.

One of Savannah's oldest and most haunted cemeteries, featuring graves desecrated by Sherman's Union Army.

"X" marks the spot of an echo chamber in the middle of a plaza.

The arch that celebrated the completion of the Lincoln and Victory highways.

The self-made house sculpture of an outsider artist who named himself "Chief Rolling Thunder."