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

The site where one of the most famous poems of World War I was composed is preserved to honor the legacy of the work.

A rare example of World War I trenches from the British front.

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

This fairytale castle was built as a show of power but was nearly torn down thanks to its history of torture.

This gruesome biblical parade celebrates the one day a year that a bit of Jesus' blood turns to liquid.

The compass on its front was a handy tool for 17th-century merchants who needed to know the direction of the wind.

Christ's blood allegedly preserved in a Belgian town.

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

This demon atop the Notre-Dame de Paris looks utterly bored.

The celebrated eyesore created by starry-eyed sweethearts.

The narrowest street in Paris.

This bridge was constructed from the rubble of the infamous Bastille.

The spiral staircase hidden inside this giant Parisian column was likely built for Catherine de Medici's astrologer.

A series of abstract, silly sculptures represent the works of a great modern classical composer.

Medieval museum built over Roman baths that features famous tapestries of a lady and a unicorn.

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

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

This modest marker near Notre Dame identifies the very center of Paris.

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

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

Notorious artist squat renovated into legal studios.