High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.

135 bronze medallions mark a French meridian line which once rivaled the hotshot Greenwich timeline.

The vast, legendary catacombs hold secrets much stranger than stacked bones.

The spiral staircase hidden inside this giant Parisian column was likely built for Catherine de Medici's astrologer.

This emotive sculpture was originally created for the 1878 World's Fair.

If you look closely at the oldest bridge in Paris, you might notice hundreds of ugly faces leering from its sides.

The celebrated eyesore created by starry-eyed sweethearts.

This bridge was constructed from the rubble of the infamous Bastille.

A tiny village in Wales claims the name of a noble medieval hound slain for a crime he didn't commit.

A miniature Italianate fantasy village on the coast of Wales and the set of ITC classic "The Prisoner."

Neolithic burial chambers hidden beside a village school.

The world's longest continuously running show has played at this small West End theater since 1974.

Cliffs full of fossils at the portal to England's Jurassic Coast.

The world's only managed flock of mute swans was established as a factory for monk meat but is now an adorable sanctuary.

A beautiful bronze statue of the greatest fossil hunter of the 19th century.

Dozens of snakes are housed and worshipped within the walls of this Vodun temple.

A mysterious pair of mice eating a piece of cheese is London's smallest public sculpture.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

Why a column on the entrance is inscribed with a verse from the Quran is one of Sicily's many mysteries.

This triumphal 16th-century arched gateway leads to the oldest street in Palermo.

Thousands of well-dressed mummies below a monastery.

An abandoned shopping gallery built during Fascist Italy tucked in the center of Palermo.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.