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

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

The quaint little store that is said to have inspired a famous Dickens novel was only given its name after the book was released.

Famously misunderstood wonder of the ancient world

A student driver's nightmare.

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

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

The sign at the garden gate reads: "These Plants Can Kill."

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

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

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

17th century streets hidden under Edinburgh were once a breeding ground for the black death.

An easily overlooked stretch of ornate window fronts and gaslight lamps that could be right from the pages of Dickens.

A 300-year-old tea shop that brought tea to the English people, not to mention the Queen herself.

This gallery commissioned by Cardinal Spada is known for its magnificent optical illusion.

Medical museum that houses most notably the taxidermied remains of Vladimir Demikhov's famous two-headed dog experiment.

The mummified relic of St. Catherine sits forever on a golden throne.

An extraordinary collection of 18th century anatomical waxworks.

Stuck in the arcade of Casa Isolani are three arrows of mysterious origins.

The wreckage of a tragic plane crash is on display at this museum devoted to a famous Italian conspiracy.

Once known for its horse-powered knife sharpening, this 200-year-old shop offers an array of blades and hard-to-find culinary tools.

The remains of an ancient Roman city are hidden underneath Bologna's beautiful public library.

In the world's oldest university is a stunning 17th century anatomical theater carved from spruce.

An amazing collection of wax anatomical models and terratological models.