A spiral staircase twists to the top of this unusual Czech lookout tower.

Two monstrous faces loom over a village in Czechia.

A 400-year-old mummified arm dangles from the ceiling of St. James the Greater, serving as a warning to thieves.

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

What looks like a suicide in progress is actually a statue of Sigmund Freud.

The first museum in the world devoted to sexual gadgetry.

A church of bones, decorated with 40,000 human skeletons.

A cemetery in Barcelona's Poblenou district is home to this touching funerary statue, which depicts death in the form of a winged skeleton.

A temple to modernity, tucked away amid Barcelona's more well known museums.

Turntable anonymously received orphans, alms, and groceries.

The only things left in this abandoned Latvian graveyard are a mysterious stone and a ghost story.

For the last century, this international border within a small town has appeared and disappeared various times.

This peculiar border irregularity is the only way to legally enter Russia without a visa.

It's rumored this unique Baltic beacon was designed by Gustave Eiffel himself.

This Estonian watchtower looks like a big tree with two giant bird nests on it, complete with a "golden egg."

A historic scientific breakthrough that crosses nine borders.

Hundreds of small crosses have been carved into the bark of the trees outside this small Estonian village.

A decommissioned submarine base makes a great space for graffiti art.

Man-made mineral caves house massive bat colony.

A trio of giant wooden megaphones turn up nature's volume in this Estonian forest.

This Cambodian riverbed is covered in ancient Hindu carvings both above and below the waters.

Witnesses claim the Virgin Mary statue outside the church once mysteriously shed a single tear.

A nightmare for the claustrophobic lies hidden in Southeast Asia.