Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

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

Hidden behind a wall for decades, this masonic lodge was only rediscovered during renovations.

A historic house left in "dramatic still life."

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

The Bristol Camera Obscura housed in an ancient windmill.

The mysterious megaliths have enchanted and intrigued visitors for thousands of years.

An ancient Scottish rock formation said to be the gravesite of a giant remains ensconced in legend and intrigue.

This striking observation tower shaped like a spinnaker sail is the newest icon in historic Portsmouth.

This star-shaped artillery fort protected the mouth of the Thames from the 16th century to the Second World War.

The abandoned fishing village was swept right into the sea.

One man spent 10 years building a spectacular section of road because no one else would.

The ruins of Scottish sea salt production.

At high tide this strange footbridge appears to have no purpose whatsoever.

It is said the legendary wizard once lived in this sea cave beneath Tintagel Castle.

This two-towered gateway is all that remains of the unluckiest pier in the world.

The ruins of a medieval seminary some say is the oldest university site in Scotland.

"The Donut" was built as part of an expensive, ill-fated engineering endeavor.

The remains of a grand castle that may have inspired Bram Stoker's Dracula.

The second-longest pier in the U.K. stretches a whole kilometer into the Irish Sea.

A real-life Professor Snape once taught in this Welsh university building, which students of course nicknamed “Hogwarts.”

The world's largest prehistoric copper mine had 30,000 animal bones scattered throughout the maze of passageways.

An octagonal folly tower overlooking the sea.