The Metropolitan Police refurbished the blue box (perhaps not coincidentally) the same year "Doctor Who" returned to TV screens.

A collection of comics, graphic novels, animation and caricatures devoted to exploring this often overlooked art form.

A mysterious artist-run cabinet of curiosities and library.

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

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

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

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

This tower is all that remains of a once-famed chapel.

A patriotic medieval knight in driven-nail armor raised money for widows and orphans of WWI.

The resting place for anonymous victims of the Danube's dark waters.

Macabre museum devoted to historical Viennese murders.

This statue honors one of Budapest's most beloved literary characters.

A 13th-century convent where St. Margaret of Hungary spent her teenage years.

A fake Transylvanian castle houses a cathedral of antlers.

A silly medieval mural preserved on the side of a Viennese house.

Legends surround an ancient tree trunk riddled with nails for good luck.

A tropical paradise just a short trip from the opera house is filled with beautiful winged creatures.

A steampunk-styled three-floor factory churning out art, activism, and electronic beats.

This classic restaurant features a gorgeous mirror-clad room.

This concrete residential area doubles as an open-air gallery.

This TV tower once secretly housed a GDR intelligence team.

This curious sculpture represents the perseverance needed to take to the skies.

A 12th-century fortress containing some of Berlin's oldest buildings.