A subterranean playground in an abandoned slate mine.

England's most notorious suicide spot.

The sixth of London's "Magnificent Seven" cemeteries, and a source of unlikely inspiration to Beatrix Potter.

Hidden behind a wall for decades, this masonic lodge was only rediscovered during renovations.

Repository for more than 22 million pickled specimens.

This hidden rooftop garden in downtown London offers a quiet respite from a bustling city.

This wildly-tiled artist's palace is a living and growing account of the creator's life, loves, and labors.

The decaying ruins of Wales' first asylum for the mentally ill.

An incarceration museum on the spot of possibly the oldest prison in England.

Shakespeare, David Bowie, Dr. Who, the Saxons, Druids and Romans are all claimed to have all made their mark on these massive man made tunnels.

Mysteriously stacked storefront paths give this medieval British town an iconic style like none other.

A Victorian natural history and ethnographic museum with wonderful turn-of-the-century, science-book-esque evolution displays.

The largest greenhouse in the world is home to over one million types of plants.

A historic London cemetery now serves as a nature park incorporating gravestones & memorial statues.

Remnants of a Victorian garden feature sitting in public woodland.

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

"Respectful to the dead, safe and sanitary to the living, dedicated to the Genius of Memory..."

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

Hear the quietest sound from across the dome.

A kaleidoscopic warehouse-maze of handmade neon signs.

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

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

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

One part local history, 99 parts gruesome haunted house.