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

An alleyway plaque is all that remains of the independent Texas' envoy that forgot to pay their rent for over a century.

A kaleidoscopic warehouse-maze of handmade neon signs.

The signs of a long buried road can still be found hidden beneath a London sewer grate.

An unusual round church in London with a Templar past.

This South London cemetery holds the remains of more than 15,000 people.

A subterranean ice warehouse that has lain hidden beneath central London for over a century is now open to the public.

This churchyard arbor is surrounded by hundreds of gravestones placed there by author Thomas Hardy.

Someone loved this song enough to carve all of its lyrics onto a tree trunk in a Berlin park.

This little museum is making sure that the art and history of the graffiti sticker is not scraped from history.

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

When German-Iraqi relations broke down, this embassy was vacated post haste.

The music is over at the Ballhaus Riviera Ballroom, but the ballroom remains in haunting disrepair.

A surreal museum of extraordinary industrial objects.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.

An eerie, derelict amusement park in Berlin.

The risqué mixed-media sculptures are supposedly a metaphor for Czech politics.

One man's personal collection of KGB memorabilia is presented along with his strange viewpoint.

Increasingly decayed figures stand as a powerful reminder of the human costs of Czech Communism.

Monument to a suicide protesting the Soviet invasion.

The tunnel's elegant proportions keep you snug with no claustrophobia freak-out.

An old asylum graveyard that's been abandoned for half a century attracts those seeking a dark thrill.

This tipsy office building in downtown Prague was originally called “Fred and Ginger.”

A Jenga-style cylindrical tower of books that appears to go on forever.