One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

From Nazi chemicals to the CIA, this architectural marvel has played a fascinating role in German history.

Islanders once used this dramatic, otherworldly landscape to hide their cattle from Viking raiders.

A rare chance to ride one of the few continuous elevators still in operation.

Martin Bricelj Baraga's monolithic sculpture measures the blueness of the sky, and changes color to match it.

A trough of 700 strange bronze faces runs through a narrow alley in Ljubljana's old town.

An otherworldly alpine pasture with its own unique microculture that recalls Middle Earth.

This one-time health resort was used by aristocrats around the world.

This spire on an Austrian mountain is wrapped around a long spiral slide and has the world's tallest wooden observation deck.

Trick water gardens from 1619 featuring a 200 piece mechanical theater powered by water.

A huge musical instrument played by the ocean.

An organ located deep within a cave, whose "pipes" are the geological features of the cave itself.

6000-year-old coal fire moves one meter per year.

The unique ecosystem atop an Australian mountain is home to some colorful inhabitants.

A huge stone pyramid built for fun.

Asbestos pit mine abandoned in 1983 is still dangerous thirty years later.