Wedged between two buildings at the Great Ormond Street Hospital is this secret music installation.

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

This hospital once pioneered the use of electroencephalograms, but fell into maltreatment, abuse, and eventual abandonment.

The world's oldest model village.

The biggest and deepest Cold War bunker open to the public can be found in southeast England.

The Florence Nightingale Museum is home to the famous nurse's most treasured possession: her beloved pet owl.

A miniature Italianate fantasy village on the coast of Wales and the set of ITC classic "The Prisoner."

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

The world's first underground farm is in a World War II bomb shelter beneath the streets of London.

The largest of London's subterranean rivers and once a mad, bad center of London life.

A naturally mummified 2,000-year-old man.

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