The intricate stonework of Machu Picchu serves as a testament to Incan engineers.

Thousands of volcanic rocks carved 1,000 years ago.

This 16th-century monastery was founded to cloister the daughters of wealthy local families.

A monument to the conquistador became increasingly controversial in the very city that he founded.

The mortal remains of an estimated 70,000 people lie in the basement of a monastery in Lima, Peru.

Only a few pieces remain of the structure that carried people and goods across the Thames for some 600 years.

The bones of two medieval royal lions were discovered at the historic fortress.

It celebrates a very stinky task and salutes London's fatberg-vanquishing team.

The plunge pool is a surviving relic of a rowdy royal residence.

An architectural oddity hides in plain sight on this iconic London bridge.

Tucked away in the Tower of London is the weapon once used to execute high-profile prisoners.

A Roman spa buried deep beneath the City of London.

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

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

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

Thanks to modern navigational tools we now know that the true prime meridian runs through a park next door.

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

One part local history, 99 parts gruesome haunted house.

This London pub hides a peculiar secret: a recreation of the rooms shared at 221b Baker Street by Sherlock Holmes and Dr. Watson.

A semi-scholarly approach to sex.

A museum dedicated to the strange and extravagant costumes and memorabilia of the mummers, a tradition older than Philadelphia itself.

America's only nuclear missile silo open to the public.

A snapshot of the city's fascinating voodoo culture.

One of the largest crucifixes in the world stands 55 feet tall in a secluded, wooded area of northern Michigan.