A charming 17th-century alley is lined with secondhand bookstores and antiquarian shops.

A cluttered and astounding collection of antiquities and curiosities.

The remains of Crystal Palace Great Exhibition of 1851.

Catacombs turned marketplace.

In this cobwebbed old operating theater, you can practically hear the screams of the unanesthetized patients.

A island reachable by a causeway at low tide is possibly one of the earliest Western European locations to be identified in text.

A fantastic castle rumored to be the birthplace of King Arthur.

The curios of pharmacist and collector Henry Wellcome.

Northern Ireland's Brobdingnagian stepping stones.

Famously misunderstood wonder of the ancient world

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

This shop and gallery is a modern-day cabinet of curiosities, unassumingly positioned along an urban thoroughfare.

A kaleidoscopic warehouse-maze of handmade neon signs.

This ornate Victorian marketplace was the setting for Diagon Alley and the Leaky Cauldron in the Harry Potter films.

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

This irregularly shaped sea fortress has defended not one but three different sovereign states.

An abstract monument to a symphonic composer.

An alien church provides much needed silence in the midst of a Finland shopping center.

A subterranean house of worship carved right out of the bedrock.

Stunning examples of Russia's 18th-century wooden architecture.

A complex of six forts embedded in the Rajasthan hills.

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

Charnel house at the foot of Mount Sinai.

An exercise in radical design and social living that became the epicenter of Soviet spy networks in London.