This gem of Moorish architecture is slowly disintegrating along the coast of this charming town.

An ancient burial ground believed to have been used for ritual sacrifice.

An ancient Phoenician citadel once stood at the site where Queen Dido first landed, according to legend.

An engineering error ensured this cavernous 350-foot-long subterranean thoroughfare was never used as intended.

A 200-year-old prison that now houses a peculiar crime museum.

A seven-century-old jail tells a not-so-pleasant history of crime and punishment.

Lumps of significant stone from around the world surround a flaming monument for peace.

The tallest outdoor elevator in Europe rockets passengers on a dizzyingly precarious ride to the top of a mountain.

This historic covered bridge contains a series of macabre paintings that communicate one thing: everyone dies.

This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

These spooky and unusual stone formations create an underworldly landscape.

There has been an astronomical clock on this spot since the 14th century.

This fascinating museum in an old water tower holds the world's largest collection of Vodou artifacts from western and central Africa.

The John Snow Memorial marks the epicenter of London's 1854 cholera epidemic.

The remains of the great moral philosopher reside in a university in London.

These wire animal sculptures commemorate the exotic inhabitants that once called the Tower of London home.

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

Where condemned pirates met their grisly end at the gallows on the River Thames.

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

This small museum in a former church crypt contains artifacts of the Elephant Man, Jack the Ripper and Florence Nightingale.

The spot where three Protestant clergymen were burned at the stake during the reign of "Bloody Mary."

Outside a market, beautiful murals pay tribute to fruit sellers and farmers, as well as a few legendary artists.

The ruins of a Roman fort lie in the shadows of an imposing medieval castle.

The other side is actually green.