This ancient theater was once the home of fierce gladiatorial battles.

The world's tallest bridge is also possibly the most elegant.

A natural arch carved by a river gave its name to the so-called "Cave of Forgotten Dreams."

This salt marsh in Southern France is as pink as the flamingos that inhabit it.

This historic island prison holds one of the dungeons from the Count of Monte Cristo even though it is a work of fiction.

Natural history museum celebrating biodiversity with a parade of taxidermy animals.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

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

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

This bell tower is the only one of its kind in the Netherlands and was a symbol of prestige.

This fairy tale forest hides scenes from some of the more obscure and bizarre Western nursery stories.

This Belgian theme park began as a refuge for bored church children and was closed down when a boy lost an arm.

This old, abandoned hotel offers magnificent views.

A pilgrimage site where people ask Saint Dymphna to watch over those who are not of sound mind.

Stocking up on the world's best beer requires a pilgrimage to a monastery drive-through.

A 141-foot wave of crashing lumber guards the entrance to the Grand Place in Mons.

A collection of weird and wonderful art fills a former houseplant nursery.

A moving memorial to the fallen and missing from WWI trenches.

A beer pipeline runs beneath Bruges.

Each time a baby is born in Ghent, these streetlights flash in silent celebration.

An open-air sewer system that was covered piece-by-piece over 300 years.

This narrow Ghent alleyway is an officially sanctioned street art tunnel.