This fairytale medieval church in Poland originally spent centuries in Norway.

What was once an underground Nazi city is now Europe's largest bat reserve.

A delightful museum entirely dedicated to the tiny homes of dolls.

A 90-ton, gravity-defiant steam locomotive shoots for the skies in this bizarrely beautiful public artwork.

This fairytale inspired, warped building houses restaurants, shops, and a radio station.

A haunting deserted hotel is a favorite with artists and photographers.

This centuries-old wooden wonder was built in less than a year and is one of Europe's largest timber-framed churches.

Crosses of all shapes, sizes and colors litter the mountain, the site of a huge yearly Orthodox pilgrimage.

This imposing 20th-century castle was abandoned before it was ever completed.

Museum dedicated to "the man who moved the Earth."

A peculiar family mausoleum built by a German nobleman captivated by the occult.

These massive moving sand dunes have swallowed an entire village and are still on the run.

A collection of old neon signs from all over Poland line a secluded courtyard.

A 20th-century picture show in 3-D.

This hidden collection of everyday objects illustrates life within communist Poland.

Communism's topsy-turvy effect on Poland has been brought to life in this wacky tourist trap.

St. Mary's features one of the most spectacularly decorated cathedral interiors in all of Europe.

A hidden art gallery in an abandoned Warsaw fort.

The site of the first battle of World War II.

A program of Communist glamour in post-Stalin Poland is preserved in this colorful museum.

An underground city of salt.

Countless stories attempt to explain Poland's mysterious J-shaped trees.

The walls and ceiling of this Polish church are decorated with thousands of skulls, with another 21,000 skeletons just below.

This 16th-century monastery has been turned into a surrealist architecture compound.