A popular shrine where the Blessed Virgin allegedly appeared in 1830, displaying a holy armchair and two incorruptible remains of Lady Saints.

Exquisite wall sculptures carved in secret by an early quarryman in an obscure corner of the Paris Catacombs.

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

This statue was given to France by the United States to commemorate the centennial of the French Revolution.

The curious underground history of keeping Paris clean.

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

The history of radiation is on safe display at the foot of a radiation science laboratory.

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

Indents in the pavement are all that remain from a grisly death machine in Paris.

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

France's most famous cemetery, with some of its most curious tombs.

Abandoned railway line circling the city of Paris.

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

An iconic waterwheel in the Pennine Hills marks the location of one of Britain’s most profitable lead mines.

Be on the lookout for the symbolic insect all over the city.

The world's first successful water-powered cotton mill paved the way for the factories of the British Industrial Revolution.

The only electricity pylon under whose legs you can go by boat.

A hunk of prehistoric lava rests amid the Gothic architecture of a campus quad.

One of the last remnants of the Bessemer process that revolutionized steel production during the industrial age.

A mysterious bridge over a sunken Roman road.

A half-mile-long stretch of medieval forts built after a devastating pirate attack persists amid the modern port city.

This innovative steam machine was no doubt the most famous of the pioneer locomotives.

This remarkably intact, 260-year-old cargo ship is only visible at the lowest of spring tides.

A mysterious demonic figure peers down from its perch within the gorgeous Chester Cathedral.