A Roman spa buried deep beneath the City of London.

This museum tucked below a charming cafe gives a brief snapshot of photographic history.

Remnants of cells from the most notorious London prison may lie in the basement of a rare Victorian Gin Palace.

19th-century scientists would make the pilgrimage here to verify the precision of their measuring sticks.

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

A historic arboretum and non-conformist, non-denominational park cemetery.

This legendary stone is of unknown origin, and throughout history has been a literal touchstone for British leaders.

A hidden treasure in London with a rich medieval history, and the resting place of many luminaries.

Six ravens are kept captive (but well-fed) at the Tower of London to prevent the fall of the Crown.

Artists and musicians now rule over this former rail station.

This massive collection of British military artifacts includes the heartbreaking personal letters of the men in the trenches of WWI.

A collection dedicated to the treatment of disease, held in London's oldest hospital.

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

Scattered throughout London are ancient remnants of the city's former bounding wall.

The Metropolitan Police refurbished the blue box (perhaps not coincidentally) the same year "Doctor Who" returned to TV screens.

Repository for more than 22 million pickled specimens.

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

One of the world's largest collections of pathological specimens.

This hidden green space is the city's second largest conservatory.

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

The remains of Crystal Palace Great Exhibition of 1851.

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

The final resting place to 300 Victorian-era pets hides inside the city park.

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