This medieval castle overlooking the Elzbach river looks just like it did hundreds of years ago.

Ruins of a German Castle on top of a towering stone pillar.

The fairy tale castle of the "fairy-tale king."

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

This leafy estate is worth $18 million and is so grand it has two mailing addresses.

A painfully obvious spy house sits right across the street from the Russian Embassy.

A wondrous old library overlooking the nation's capital.

Enormous piles of historically significant stones, dumped by Congress in a forest, and abandoned for 60 years.

Home to items never before seen by the public.

Dr. Strangelove-esque tours reveal the inside a bunker once reserved for Stalin himself.

The maximum security facility was once thought to have "the bloodiest 47 acres in America."

The winter home of thousands of beautiful snow geese and sandhill cranes.

This romantic, decaying 13th-century ruin on the edge of Sherwood Forest is reputedly one of England's most haunted places.

Six times a day a train runs right through the middle of this Thai street market, sending vendors scrambling.

This 1920s Dutch barge is now a floating bookstore.

The ruins of an 11th-century Norman castle with a rare, perfectly circular shape.

This historic little railroad runs through some of the most beautiful scenery in Germany.

A rare example of World War I trenches from the British front.