Medicinal spa created with the discharge from a geothermal energy plant.

An encyclopedic collection of mammal penises.

One of the tallest buildings in Iceland, and perhaps, the most visually impressive.

Rare collection of medieval books under lock and key.

The largest known medieval map of the world.

Beasts and branches swirl in sandstone carvings, interrupted by one strange creature.

This bridge is the first to be made entirely from iron, but designed like it was still made of wood.

The largest stone circle in the world has ended up bringing up more questions than it has answered.

This antique prison is a tourist attraction with a sordid past.

Famously misunderstood wonder of the ancient world

Stroll through Welsh history in a village of reconstructed structures.

Go deep down into the earth to experience the world of Welsh coal miners.

This well-preserved Cistercian Abbey in a romantic pastoral setting has inspired artists like the poet Wordsworth.

Detailed sandstone carvings show an array of symbolism and adorable animals.

Amsterdam's Red Light District leaves little to the imagination.

The handiwork of a underdog clockmaker who solved an impossible problem for an Empire, and forever revolutionized seafaring.

A museum wholly devoted to juvenescence.

After nearly 60 years, there's still a bear at Paddington Station looking for help.

London's last remaining public soapbox site has seen speeches from Karl Marx, Vladmir Lenin, and George Orwell.

Thanks to modern navigational tools we now know that the true prime meridian runs through a park next door.

Charles Babbage's proto-computer, painstakingly brought to life.

This small museum in a former church crypt contains artifacts of the Elephant Man, Jack the Ripper and Florence Nightingale.

Eighty million natural history specimens call this gargantuan museum home.

This massive collection of British military artifacts includes the heartbreaking personal letters of the men in the trenches of WWI.