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

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

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.

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

The Great Fire of London and the regulation of one-way streets both started in this alley.

The commemorative stone column conceals a secret laboratory.

Hear the quietest sound from across the dome.

Its collection includes a broad array of social, geographic, graphic design, and political history.

A mysterious shape catches the eye in this 16th-century painting.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

The blinking light atop the iconic landmark has been sending secret messages for decades.

These delicate buggers are some of the rarest fossils that have bubbled up from the Tar Pits.

Scores of vintage street lamps shine along L.A.’s Miracle Mile.

A music-filled, booze-soaked oasis in the desert.

A fake town founded by Western movie stars is now becoming a hip desert community.

A hotel and restaurant serving as the mecca of kitsch.

Aqueducts have dramatically changed this old lake, now home to tufa towers and its very own species of tiny brine shrimp.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

Charleston's historic city jail once held everyone from pirates to Civil War POWs.

One of Savannah's oldest and most haunted cemeteries, featuring graves desecrated by Sherman's Union Army.

An eerie smiling woman looms above the granite tombstones.

Arrr! The most authentic collection of pirate artifacts in the world... matey.

The walls of America's oldest masonry fort famously "swallowed" cannonballs.