A mysterious castle built as a monument to lost love.

This former luxury resort in Kaua'i is now an abandoned relic.

This blowhole is supposedly caused by a trapped monster.

This modern castle sat empty for decades before a fire inspired its builders to complete its luxury halls.

Moonbows over Kentucky.

The world's longest known cave system.

Pensacola's UFO home has withstood many hurricanes—just as the experimental 1960s design intended.

One of the only Florida forts to remain in the hands of the Union all through the Civil War still stands as a historic stronghold.

Florida’s half-sized replica of the Vietnam Veterans Wall.

A local landmark with generations of spraypainted messages, and more being added each day.

An unsanctioned shrine that sprung up outside the late singer's home is causing a stir in London's Highgate neighborhood.

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

The cedar tree in Highgate Cemetery earned its title by accident.

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

One part local history, 99 parts gruesome haunted house.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

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

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

Abstract dinosaur models in London.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

This shop and gallery is a modern-day cabinet of curiosities, unassumingly positioned along an urban thoroughfare.

An artistic tribute to the famous singer, just around the corner from where he was born.

This artist's home turned gallery/museum preserves the creator's love of "Eastern" influences.

A 300-year-old tea shop that brought tea to the English people, not to mention the Queen herself.