Perhaps the only one of its kind, the nearly-forgotten site once held mortal (and rigged) gladiatorial games between tigers and imperial war elephants.

Hear the quietest sound from across the dome.

Hidden behind a wall, Spanish nuns distribute their signature sweets on a revolving tray.

Its appearance in "Game of Thrones" may spur on the long-awaited restoration of this medieval shipyard.

The world's largest wooden structure.

A collection dedicated to the treatment of disease, held in London's oldest hospital.

A portly statue of a golden boy commemorates an unusual cause of the Great Fire of London: the sin of gluttony.

The taxidermied remains of a once-great parrot.

Down a pint of ale where the Bishop of Ely's servants slept in 1546.

This landmark church concealed a crypt packed with bones that was discovered thanks to the London Blitz.

One of the few remaining examples of 19th-century London’s attempt to clean up its reputation.

Dictionary Johnson’s favorite feline.

The obelisk honors the cyclist troops who were killed during World War I.

Stunning Roman aqueduct used for 1900 years and still standing.

Long tunnels run under the ancient chariot racing circuit to the tower.

This Roman arena once played host to bloody gladiatorial battles.

This magical space partly designed by Antoni Gaudi is one of the best examples of romantic gardening in the Mediterranean.

Extensive Orthodox icon collection in Andorra.

Some of the smallest works of art in existence.

A great example of the inventive canal bridges that were deliberately split down the middle.

This medieval manor house was equipped with secret compartments for hiding priests.

Some wattle-and-daub, a Moorish mural, a glacial erratic, and a Giant named Gilbert.

An ancient woodland that inspired a young J.R.R. Tolkien.

This postmodern apartment block was designed to be a vertical neighborhood.