An Italian hillside ghost town.

People have been living in the cave houses on this Italian hillside since the Neolithic era.

Ruined castle with subterranean vaulted Goblin Ha' or "Goblin Hall."

At high tide this strange footbridge appears to have no purpose whatsoever.

This bronze statue was erected to honor a small Scottish town's beloved stray cat.

Every St. Andrews student knows to avoid this inscription for fear of a martyr's curse.

This palatial spiral staircase was so unusual the name "snail" was given to the noble family who built it.

A beautiful collection of taxidermy birds and rare pomological wax models.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

This Austrian museum celebrates the work of famous forgers and their inimitable imitations.

Museum devoted to the artificial language of Esperanto.

Handsomely crafted representations of our round planet.

Legends surround an ancient tree trunk riddled with nails for good luck.

The beautiful, ornate weather station is the most popular geocache in Salzburg.

Ruins of a German Castle on top of a towering stone pillar.

The stunning interior of this Gothic church is covered in ornate gold details.

The medieval castle built as headquarters for the Pope's secretive Knights Templar.

London's smallest police station is barely the size of a phone booth.

Remnants of the most densely packed city in world history, that thrived on anarchy for 30 years.

Museum dedicated to literary greats of the Romantic Period is also the home in which Keats met his untimely end.

The martyr's wax-enhanced skeletal remains lie preserved in a glass case in the Santa Maria della Vittoria in Rome.

The studio built by fascists in the hopes of "reviving the film industry" with the occasional propaganda film opportunity thrown in.

Ruins of a 10th century church tucked away deep in a botanical garden.

A town saturated in Italian rationalist architecture was once marshland drained by Mussolini.