A network of concealed passageways lies within a busy London Underground station.

This abandoned gun tower was built to defend the River Thames from a French naval attack.

Climb to the top of this windmill for a scenic panorama and up-close look at wind energy production.

According to the locals, the sands of this secluded Norway beach are infused with gemstone particles.

The only electricity pylon under whose legs you can go by boat.

Only spot in the world where an HVDC powerline, a single phase AC and a three phase AC powerline all meet.

This peculiar border irregularity is the only way to legally enter Russia without a visa.

Old-fashioned knowledge and modern engineering create the world's only rotating boatlift.

In the northernmost city in the world, it's illegal to be buried because it’s too cold for bodies to decompose.

Cold storage for agricultural biodiversity.

This antique thermometer honors the creator of the first universal temperature scale.

Remote, volcanic island that Darwin, Hooker, and the Royal Navy shaped into a thriving, artificial ecosystem.

Six turbines towering over a wide road for passersby.

The Isle of Wight’s “Island Line” serviced by former London Underground trains from the 1930s.

The site of one of the largest non-nuclear explosions in history, created when a massive bomb dump accidentally exploded.

On a site with a long military history, a 1980s shelter.

One of the last doorless, continuously moving elevators still in use in the U.K.

A quartet of rusting satellite goliaths are all that remain of a communication network that protected Britain from German and Russian air strikes.

This disused Cold War bunker has been restored to all of its early 60s glory.

A rotting air force base is now home to rare birds and scarce plants.

This charming railway is one of the oldest and steepest funiculars in England.

A 550-square-meter micro-nation off the coast of Britain.

The biggest and deepest Cold War bunker open to the public can be found in southeast England.

A petite castle folly in the English countryside.