The secret wartime bunker built on the platforms of an abandoned Tube station.

The pretty iron lamp is a reminder of the architecture underneath London's streets.

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

England's most famous front door has an accidental doppelganger.

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

A historic London pub with prison cells in the cellar and a "spy room" on the second floor.

A traditional American farmhouse plopped in the middle of a Piccadilly courtyard.

These official units of measurement—including chains and perches—lie hidden beneath tourists' feet in a popular London hub.

The medieval woodcut-style artwork chronicles life in medieval London.

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

The world's oldest optical museum is an odd collection where the exhibits look at you.

An alleyway plaque is all that remains of the independent Texas' envoy that forgot to pay their rent for over a century.

Claiming to be the oldest hat store in the world, this historic haberdashery had a hand (and a head) in the creation of the Bowler.

Several plaster noses are hidden in plain sight around London's Soho neighborhood.

This striking statue brings a scene from the African savannah into central London.

These ornate arches show how the course of the River Thames has changed.

This London pub hides a peculiar secret: a recreation of the rooms shared at 221b Baker Street by Sherlock Holmes and Dr. Watson.

The bronze uniforms commemorate the vital role of women during World War II.

This recreation of a 19th-century dime museum is full of oddities.

A diorama of the Civil War, fought by cats.

The United States' oldest Episcopal church still in active use.

A dramatic, 360-degree recreation of Pickett's Charge in the Civil War.

The Cold War-era "underground Pentagon" is a sprawling subterranean hideaway for the Defense Department.

Extraordinary objects lurk in this quintessential regional museum.