Giant origami sculptures tucked into desert scenery beckon passers-by to explore further.

Life-sized sculpture of a blue whale made of hand-recycled plastic trash.

A sprawling collection of over 106,000 toys from around the world.

This high desert botanical garden is a unique display of Northern New Mexico's geology.

This innocuous New Mexico storefront was once the secret jump-off spot for Manhattan Project scientists.

One of the world's largest collections of pathological specimens.

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

This pump on the bad side of Victorian London betrayed a horrifying revelation about the water supply.

A Roman spa buried deep beneath the City of London.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

A mysterious pair of mice eating a piece of cheese is London's smallest public sculpture.

The site of London's first coffee house has been serving refreshments of one kind or another for 360 years.

Hear the quietest sound from across the dome.

This landmark church concealed a crypt packed with bones that was discovered thanks to the London Blitz.

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

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

One part local history, 99 parts gruesome haunted house.

A hidden path at the National Theatre lets you look behind the scenes of the latest productions.

This open-air mosaic gallery honoring an English artist took hundreds of volunteers more than seven years to create.

The Florence Nightingale Museum is home to the famous nurse's most treasured possession: her beloved pet owl.

A mysterious artist-run cabinet of curiosities and library.

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

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

The "beautiful" equation predicting the movement of all electromagnetic particles is engraved in front of Newton's tomb.