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

Scattered throughout London are ancient remnants of the city's former bounding wall.

London's last remaining public soapbox site has seen speeches from Karl Marx, Vladmir Lenin, and George Orwell.

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

This one has sailed five times as far as Sir Francis Drake's famous ship.

The curios of pharmacist and collector Henry Wellcome.

An incarceration museum on the spot of possibly the oldest prison in England.

Rebuilt remains of a temple to Roman god Mithras.

This massive collection of British military artifacts includes the heartbreaking personal letters of the men in the trenches of WWI.

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

One part local history, 99 parts gruesome haunted house.

The last physical evidence of the Lewis and Clark trail is one of their autographs etched into this giant rock.

A sculpture made of 10 Cadillacs as a monument to the "Golden Age" of the American automobile.

The granddaddy of all tourist traps, built on ice water, jackalopes, and a giant dinosaur.

Thanks to a loophole in property ownership, this alleyway has become a cacophonous street gallery.

Every president in history is immortalized in bronze in downtown Rapid City.

Wedding chapel's mysterious spiral staircase said to be miraculously constructed.

A small metropolis of Pueblo cave dwellings have been carved right into the hillside of this national monument.

This popular pilgrimage site offers a hole filled with holy healing dirt.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

An experimental, automotive replica of Stonehenge.

The scene of one of the darkest moments in American labor history has been left essentially untouched since the tragedy.

This prison-turned-museum is a remnant of the Old West's grizzly, violent past.

Possibly the world's only drive-in movie theater with an attached motel.