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

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

It's forbidden to dig within this ancient Roman fort hidden beneath a playground.

This small museum collects the Christian remembrances which would otherwise be forgotten.

This public library and its impressive collection of academic books have not changed since the 17th century.

A market built atop boats is one of the few floating holiday markets in Europe.

Devious political maneuvering and four ancient, working telescopes are central to the world's second-oldest observatory.

This Dutch art piece became a Russian icon.

Science meets wall art to highlight the beauty of famous mathematical equations.

The works of poetry's biggest names grace the walls of the city of Leiden, all carefully painted by hand.