Catacombs turned marketplace.

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

The John Snow Memorial marks the epicenter of London's 1854 cholera epidemic.

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

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

A toy store with a century-long history preserves the craftsmanship of playthings of the past.

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

A cluttered and astounding collection of antiquities and curiosities.

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

The curios of pharmacist and collector Henry Wellcome.

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

The anatomical-pathological collection of a man who changed surgery.

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

Picnic on the seashore in the footsteps of ancient kings, protected by giant mythical cat beasts.

This ancient Hindu temple is covered in thousands of colorful statues and has a long mythological history.

An ancient iron pillar in Delhi that seems to be rustproof.

Fifteen Jodhpur queens left their handprints before going to their fiery death.

Once an indicator of social class, the color blue has come to define this city on the edge of the Thar Desert.

A blooming house of worship for the masses.

Deep in the Thar desert, a temple crawling with thousands of holy rats.

A complex of six forts embedded in the Rajasthan hills.

More than half of this Indian palace is drowned but it looks all the more spectacular for it.

Sacred Indian temple that’s all monkey business.

The world's second-largest sundial, made entirely out of stone.