This cave holds a surprisingly colorful variety of geological oddities.

These Great Lakes sea caves accessible by boat in the summer turn into temples of ice reachable by foot in the winter.

A bizarre house filled with an astounding array of collections.

A deserted hodgepodge of experimental structures designed by nearby university students.

The black lab that was voted mayor of a California town is forever remembered by a life-size statue.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

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

There's an exclusive Beefeaters pub hidden in the Tower of London.

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

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

A naturally mummified 2,000-year-old man.

Hear the quietest sound from across the dome.

The taxidermied remains of a once-great parrot.

An unusual round church in London with a Templar past.

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

A statue marks the exact spot where The Boy Who Never Grows Up made his first literary appearance.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

Legacy of the earthquake that nearly wiped Lisbon off the face of the Earth.

The world's oldest bookshop still in operation.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

This fairy-tale, neo-Gothic church in the Azores is a world of magical realism.