One of the most easily accessible examples of the rare 1960s UFO houses.

The relics of dozens of martyrs are stored in a single chapel.

An unusual "skull with ears" sits in the crypt of this small church tucked away at the end of a narrow alley.

An eerie, little-known Neapolitan museum filled with preserved human remains.

The burial place of an obscure North African saint was turned into a macabre body preservation factory for the 17th-century Neapolitan elite.

The once forbidden "secret cabinet" of erotic art from excavations of Pompeii and Herculaneum.

Beautiful views and Roman-style statues on the Italian coast.

This clifftop arch is a natural stunner.

A former Roman town that was once the home of Scipio Africanus.

This shining multicolored metro station deep under Naples is said to be the most beautiful in Europe.

This one-time health resort was used by aristocrats around the world.

From Tintin to the Smurfs, Europe's greatest graphic icons are celebrated in a grand Art Noveau gallery.

Each time a baby is born in Ghent, these streetlights flash in silent celebration.

This narrow Ghent alleyway is an officially sanctioned street art tunnel.

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

The world's first and only escalator for lazy bicycles and their daunted riders.

This massive fiberglass Gulliver turns every visitor into a Lilliputian.

This amazing example of Valencian Art Nouveau looks more like a cathedral than a public market.

Of the many chalices in the running for the Holy Grail, this one in Valencia Cathedral sure looks the part.

Thanks to a spelling mistake this bizarre beaver-tiger hybrid became the symbol of a Siberian town.

One of the world's tallest statues is also one of its most hated.

Scattered throughout London are ancient remnants of the city's former bounding wall.

A subterranean ice warehouse that has lain hidden beneath central London for over a century is now open to the public.

This London pub hides a peculiar secret: a recreation of the rooms shared at 221b Baker Street by Sherlock Holmes and Dr. Watson.