This skewed English house has looked like it's going to fall over for centuries.

Built by the patron saint of illusionists this Elizabethan manor house is riddled with secret cubbies for hiding priests.

Described by William Wordsworth as a "World of Wonder."

This volcanic plug boasts the longest recorded history of any Scottish stronghold.

One of the world's oldest trees comes with a Welsh legend intertwining it with a spirit prophesying death.

The abandoned funicular tunnel was a secret base for the BBC during World War II.

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

Sometimes an island, sometimes a rocky outcropping connected to the world by a tiny suspension bridge.

A petite castle folly in the English countryside.

Huge concrete structures designed as an early warning system for Britain to detect enemy aircraft.

Each spring this woodland floor is carpeted with purplish flowers as far as the eye can see.

This antique prison is a tourist attraction with a sordid past.

Where the sleeping monsters of Scotland's oil industry are left to rust.

This logic-defying 16th-century Tudor manor still stands to the delight and astonishment of onlookers.

Near Birmingham, England three and a half miles of top-secret tunnels housed a World War II “shadow factory” and a Cold War nuclear bunker.

One of the few standing Roman lighthouses and a labyrinth of tunnels are a couple of the secrets at this historic castle.

This waterfall is one of the most spectacular natural features in the Scottish Lowlands.

The oldest residential street in Europe also features an optical illusion.

One family's environment-friendly hobbit-house in Wales.

Modern megaliths form this work of cosmic, Celtic landscape art.

The abandoned transportation hub hides within the Glasgow attraction it once served.

On October 17, 1814, a 15-ft. wave of beer ran rampant through the streets of London.

These steps offer a breathtaking view of one of Europe's most besieged fortresses.

A long, winding trek rewards you with a gorge so captivating it inspired a painting in the Tate.