A modern-day Lascaux cave underneath Paris.

In the best of all possible worlds, everyone will get a chance to see this statue in which Voltaire's heart is interred.

The subterranean "lake" below the Paris opera house inspired the Phantom of the Opera's lair.

A majestic lion statue guards this Parisian botanical garden, and feeds on an unsettling item.

The water-powered carriages are long gone, but for over a century this funicular railway has been the fastest route to the highest point in Paris.

The ruins of a Duke's bucolic dream, where camels once roamed alongside "Dutch" windmills and faux-Italian vineyards.

A favorite Paris bar for U.S. expats, including Gershwin, Hemingway, and James Bond.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

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

Paris' linguistic guide to the international language of, yes, love.

A scandalous Art Nouveau collaboration that set Paris all atwitter at the turn of the century.

A counter-culture bookstore like no other hides in plain sight in the streets of Paris.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

Abandoned railway line circling the city of Paris.

Makers and sellers of the original and finest York Ghosts.

This bronze statue stands throughout the year and illustrates an urgent message about the environment.

Three tiny islands in a Portsmouth pond are at the center of disputed land claims from a number of competing micronations.

This colossal war machine is now a living museum dedicated to underwater warfare.

This striking observation tower shaped like a spinnaker sail is the newest icon in historic Portsmouth.

Old Tudor home moved on thick iron rails to a new spot.

At just 25 inches at its narrowest point, it's one of the tightest streets in the world.

These medieval tunnels provided water to the city above through centuries of civil war and plague.

The construction of this bridge dates back to the 15th century.

This small record store was a favorite of Oasis's Noel and Liam Gallagher, who mentioned it in one of their early songs.