A sandstone block marks the alleged spot where the legendary writer was conceived.

A neighborhood church's unusual abstract stained glass was the final project of avant-garde artist Jean Cocteau.

Two standing giants remain as a tribute to Luxembourg's metallurgical past.

The remains of 40,000 humans, meticulously stacked in a tiny churchyard shed.

A monument to the thousands of Canadian soldiers who died capturing the French ridge during World War I.

This former cannon foundry and castle for the Counts of Flanders is now a public garden.

This triumphal arch celebrating the Sun King's conquest of Lille is a masterpiece of military architecture.

This monumental mural crafted nearly 40 years ago is still in perfect condition.

This bunker in northern France was built by Nazi German forces with the intention of launching up to 50 V2 rockets at London each day.

This French "sea of rocks" is packed with stunning rock formations and its own medieval castle.

The post-apocalyptic remnants of a bucolic town ruined by a plane crash.

Despite being considered a thoroughly American sport, basketball's oldest surviving playing field is found in the basement of a Paris YMCA.

The Argonaute submarine was the French navy's pride and joy in the 1950's.

This structure atop a craggy cliff in one of the most beautiful parks in Paris boasts an unbeatable view.

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

The curious underground history of keeping Paris clean.

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

A modern-day Lascaux cave underneath Paris.

This Parisian gem is one of the most incredible ethnographic museums in the world.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

This recessed garden protects thousands of mountain plants by creating its own microclimates.

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

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

This mural painted by Keith Haring was done without payment as a gift to entertain the children at the Hôpital Necker.