Rebuilt remains of a temple to Roman god Mithras.

A vast overgrown cemetery, once known as one of London's "Magnificent Seven."

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

Amazing and mysterious Neolithic settlement on Scotland's Orkney Islands.

A student driver's nightmare.

One part local history, 99 parts gruesome haunted house.

The only university zoological museum in London houses extinct animals, bizarre natural history specimens, and a Micrarium of microscopic creatures.

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

This London pub hides a peculiar secret: a recreation of the rooms shared at 221b Baker Street by Sherlock Holmes and Dr. Watson.

An unusual round church in London with a Templar past.

The longest hedge maze in the world.

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

Banksy gives themself artistic license with this piece of London street art.

A 30-acre garden inspired by the principles of modern physics.

Winding paths and ramshackle mausoleums in the oldest "park cemetery" in London.

The perfectly preserved underground rooms where Churchill plotted the war against Germany.

Northern Ireland's Brobdingnagian stepping stones.

The popularity of Sherlock Holmes led to the creation of his fictional address, turning the orderly London street numbers askew.

This collection of illusory paraphernalia has been culled from the history of London's premier magician's club.

The atmospheric road was never meant to be so creepy.

Famously misunderstood wonder of the ancient world

The hidden "ballroom" under a mansion lake was built by a criminal who ate a cyanide pill during his trial.

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

This churchyard arbor is surrounded by hundreds of gravestones placed there by author Thomas Hardy.