Places NailsNathan Wants to Go

From toys to kettles to scientific instruments, this German museum celebrates the beauty of 20th century design.

An abandoned NSA listening post on Berlin's "Devil's Mountain."

A fascinating insight into daily life in the Eastern Bloc.

A museum dedicated to the history of a terrifying secret police is now held in their former headquarters.

A surreal museum of extraordinary industrial objects.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

This piece of early engineering is rather unknown despite its location in the heart of Madrid.

A thorough look at the development and history of the underground's rolling stock of the Madrid subway system.

Meant to resemble a massive tree, the building is the best example of Spanish organicist architecture in Madrid.

A pair of gigantic baby heads greet passengers at Atocha Station.

Strange masks and obscure costumes are housed in this old Madrid corrala.

This postmodern apartment block was designed to be a vertical neighborhood.

This small and often-overlooked museum holds some of Spain's finest artistic treasures.

This lucky bronze frog was gifted to Madrid by a casino.

The only urban monument in the world designed by the great surrealist painter Salvador Dalí.

This amazing abuela became a diehard metal fan late in life and an icon of Madrid's '80s rock scene.

The morbid items in this small and hidden museum are not for the weak stomached.

A whimsical brother of the nearby Fallen Angel statue takes the falling part quite literally.

Abandoned for decades, trains still pass through the now-restored remains of one of Madrid's first metro stations.

An eclectic collection of thousands of items owned by the sculptor Frederic Marès.

On the wall of this medieval walkway, a symbol of the Spanish Inquisition.

For one day every month Barcelona's Estació de França transforms into a market for model trains.

The former 1920s mansion of a prominent Catalan developer was used as the Soviet Embassy during the Spanish Civil War, and there is still a bunker below the garden.