Beneath the impressive baroque cathedral that rises from the center of Berlin lies the largest collection of Prussian royals in the world.

A tree-like building perches on its trunk in the Steglitz neighborhood of Berlin.

Berlin's natural history museum houses the world's largest mounted dinosaur and the late beloved polar bear Knut.

A fascinating insight into daily life in the Eastern Bloc.

Possibly the world's largest hourglass only needs to be reset every New Year's Eve.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

A 19th century artistocrat's mansion, turned into a library, hidden in a modern library.

Once the home of a hermetic monk, this cave now houses a small church.

A series of caves under Castle Hill that once held the prisoner Vlad Tepes, better known as Count Dracula.

The largest bell in the world has been swinging high above a Cologne cathedral for almost a century.

A slice of central Asia in the middle of Berlin.