Hidden beneath the streets of London is a secret subway that only carried mail.

The oldest working Brewery in Britain.

A million and a half tons of earth were used to create one of the world's largest land sculptures.

The ghosts of Britain's telecommunication past sit rusting away in a small village in England.

A quartet of rusting satellite goliaths are all that remain of a communication network that protected Britain from German and Russian air strikes.

An abandoned tank sits in an empty London lot as a symbolic middle finger to local city planners.

This haunting stone chasm is a hotbed of mossy rock and English legend.

The largest cave chamber in Britain—big enough to fit a whole cathedral inside.

A metal tree emits eerie, melodic notes on top of Lancashire's Crown Point.

Unusual British home built to disguise a water tower.

The mysterious, fantastical woodland inspiration for "The Lord of the Rings."

A kaleidoscopic warehouse-maze of handmade neon signs.

London's smallest police station is barely the size of a phone booth.

A hands-off space for graffiti artists to hone and display their skills.

Kings Cross Station pays tribute to its role in Britain's best-selling book series.

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

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

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

A mysterious pair of mice eating a piece of cheese is London's smallest public sculpture.

Eighty million natural history specimens call this gargantuan museum home.

Catacombs turned marketplace.

360° views of the city plus five floors of optical illusions and hands-on science.

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

These fantastically named natural pools look like something out of a Scottish myth.