The only royal palace on U.S. soil has been a territorial capitol, a military headquarters, and a prison for a queen.

The last standing piece of a famous Honolulu landmark.

Richard III supposedly disposed of his nephews' bodies here in an effort to seal his claim to the throne.

Graffiti from the 16th and 17th centuries cover the walls of this part of the Tower of London.

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

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

The watery entrance for condemned prisoners heading to the Tower of London is still visible along the Thames.

This unassuming alcove in London’s famous Tower Bridge once served to capture, store, and display dead bodies from the River Thames.

The discovery of these rare, ancient artifacts led to the creation of a new museum.

Ancient Phoenician and Roman tombs carved into the rock overlook the Moroccan coastline.

Once close to extinction, there is no shortage of elephant seals on the beaches of Año Nuevo State Park.

Elephant seals and sea lions have turned the abandoned buildings on this island into their endangered love shack.

A strange house built only at night, with rumored mystic inspiration.

Housed in a memorial lighthouse, this museum relays the history of surfing, beginning with the antics of royal Hawaiian teenagers.

After the Cuban Revolution, the famous rum company had to leave their swanky headquarters behind.

Once a favorite playground for the world's most illustrious guests, Hotel Nacional's secret weapons and bunkers reveal a more menacing side to its golden history.

When the Cuban government seized a Trader Vic's franchise, they unknowingly led to its preservation.

A focal point of the Cuban government, this city square features one of the most iconic images in the country.

In terms of history and architecture, this is one of the most remarkable cemeteries in the world.

His music once banned in Communist Cuba, John Lennon is now immortalized in bronze by Castro, who considers Lennon a "fellow dreamer."

The last street in Pittsburgh that's paved with wood.

Meet your friends, marry your true love, or tell your enemies to kiss your butt under this historic Pittsburgh timepiece.

This quarter-mile tunnel under the Bluff in Pittsburgh bends at a 45-degree angle.

The last remnants of Fort Pitt also hold the distinction of being the oldest structure west of the Allegheny Mountains.