The first green space constructed on an elevated viaduct.

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

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.

Indents in the pavement are all that remain from a grisly death machine in Paris.

London's smallest police station is barely the size of a phone booth.

Rebuilt remains of a temple to Roman god Mithras.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

Several plaster noses are hidden in plain sight around London's Soho neighborhood.