This quaint Hungarian railway system is operated exclusively by children between the ages of 10 and 14.

A Jenga-style cylindrical tower of books that appears to go on forever.

The jaw of one of humankind's earliest ancestors on display at an overlooked geology museum.

Living trees form the structure of an open-air palace.

Gardens representing parts of Asia, Europe, and the Mid East are tucked away among the Soviet-style buildings in East Berlin.

A state-of-the-art medical facility from the Imperial era is now a derelict ruin.

The most visited, and possibly most controversial, museum in Germany.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.

Started as a kitchen garden, now the second largest botanical garden in the world.

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

The patron saint of spinsters grasps a container of dried blood.