Hear the quietest sound from across the dome.

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

The fences outside some of South London's estates are made from recycled World War II stretchers.

A tiny replica of the iconic London landmark hides on the side of the steel structure.

This mysterious and unique painting is filled with symbolism.

The sumptuous ceiling was one of the last things Charles I saw before his execution.

More than a million titles fill the labyrinthine shelves of this prestigious private library.

This overlooked street light once served as a KGB dead letter box.

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

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

The only university zoological museum in London houses extinct animals, bizarre natural history specimens, and a Micrarium of microscopic creatures.

An small and easily overlooked archaeology museum chock full of Egyptian artifacts.

The library houses an incredible collection of some of the world's most impressive books and manuscripts.

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

This coffee shop lies hidden beneath a historic church.

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

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

Colorful murals by Jean Cocteau hide within this peaceful London sanctuary.

One of the few remaining examples of 19th-century London’s attempt to clean up its reputation.

Banksy's image of a naked man dangling from the window of a sex health clinic.

Recently restored menagerie of Victorian-era beasts.

A harem-inspired Moorish fantasy design in a Victorian-era Welsh castle.

This pedestrian walkway cuts through a cemetery and over several burial vaults.

19th century museum with an eclectic mix of curiosities, from Egyptian artifacts to items on archery history to the skull of the world's oldest horse.