A subterranean playground in an abandoned slate mine.

A unique waterfall that some believe attracts the fairfolk.

Once thought to be the mysterious work of a witchy prophetess, a well with unusual properties turns objects into "stone".

An Oxford museum where visitors can have tea with the Mad Hatter and climb through the wardrobe to a fantasy land.

Surreal riveted sea forts once protected the Kent shores from German attack.

This tangled English forest looks like something right out of a fairytale.

A 1,215-foot tunnel transports pedestrians beneath the River Thames.

A fantastic castle rumored to be the birthplace of King Arthur.

The most iconic structure in Scotland has been home to bishops, colonels, and Sean Connery characters.

The world's largest collection of witchcraft regalia.

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

The unusual clock on this 18th-century market building has an extra minute hand for "Bristol time."

There's a labyrinth of manmade tunnels stretching for over an acre beneath Bristol.

This quaint mortuary chapel hides a stunning Celtic Revival and Art Nouveau interior.

A dark Victorian well house now plays host to mystical waters and pagan shrines.

With lush plants and flowers, huge trees, ponds, and hidden monuments, this place feels a bit like discovering Narnia.

Below a historic English market town lies a secret underground city complete with kitchens, laundries, storerooms, and an underground lake.

The largest stone circle in the world has ended up bringing up more questions than it has answered.

It's believed King John of England stayed at this 13th-century castle before riding off to sign the Magna Carta.

In 1943 the British military took control of this village, telling residents they had to leave temporarily. The villagers were never allowed to return.

This stream-carved gorge has inspired poets, hidden smugglers, and trained soldiers, all without losing its beauty.

This purpose-built dinosaur museum is shaped like a pterodactyl and holds fossils that were found in its very village.

This shell of a historic manor house on the Isle of Wight is said to be the most haunted site on the island.