The ruins of this Dutch castle sit atop a labyrinth of once-secret tunnels and passageways, dating back over 900 years.

This Netherlands museum holds a gloriously mechanical collection of ornate musical automata.

This beautifully designed star-shaped fort was the premier defense system of the late 1500s.

Birthplace of the "Cat in the Cradle" and a cluster of iconic, original windmills that let the Dutch tame the seas.

A former plague hospital turned medical museum.

Hidden within a Netherlands crater is a stone bed that lets those who lie in it see the sky as a curved surface.

A beautiful maze marks where three countries meet.

Peek through a transparent pyramid and drink in the mountain made of books.

This small town in the Netherlands has no roads but instead, miles of canals and over 100 bridges.

An Amsterdam street lined with antique shops each one dedicated to a different obscure collection.

From Coke II to Google Glass, this exhibit features some of the most spectacular commercial flops.

Home to items never before seen by the public.

Ask nicely, and stewards of a centuries-old charitable tradition will give you free bread and beer.

The mysterious, fantastical woodland inspiration for "The Lord of the Rings."

This churchyard arbor is surrounded by hundreds of gravestones placed there by author Thomas Hardy.

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

Rare collection of medieval books under lock and key.

The largest known medieval map of the world.

In this Borneo cave, it's not the thousands of bats you need to worry about, it's the blankets of roaches.

An underwater statue of Christ blesses the depths off Key Largo.

One of the most poignant ruins of the Chernobyl nuclear disaster, the local football team's stadium has been quickly reclaimed by nature.

This attraction was abandoned after the Chernobyl disaster.

An old hill fort covered in over 100,000 crosses is a symbol of Lithuanian nationalism and beliefs.

Located in a veterinary school, this macabre exhibit displays the effects of animal diseases.