This symbol of the French Revolution still stands where it was first planted during the 18th-century.

This unique bridge curls up like a caterpillar to let boats pass and then unfurls again to span a small canal.

This landmark church concealed a crypt packed with bones that was discovered thanks to the London Blitz.

The John Snow Memorial marks the epicenter of London's 1854 cholera epidemic.

Collection dedicated to brands, packaging and advertising.

An small and easily overlooked archaeology museum chock full of Egyptian artifacts.

The television series' iconic giant foot was borrowed from this classical painting.

A hands-off space for graffiti artists to hone and display their skills.

The world's first underground farm is in a World War II bomb shelter beneath the streets of London.

A visionary precursor to the Internet made of index cards.

This collection of over 50 murals celebrates Brussels' rich history as the self-proclaimed home of the "comic strip."

An underground paleo-Christian burial site composed of the remains of several cemeteries and Basilicas.

The storefront of a ramshackle Parisian puppet theater.

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

135 bronze medallions mark a French meridian line which once rivaled the hotshot Greenwich timeline.

In this Parisian garden's grotesque former life as a zoo it fed exotic animals to the bourgeois and put humans on exhibit.