This small chapel is built of human bones and decorated with a golden skeleton.

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

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

Ruins of a late 1950s Polish ski jump ramp in the middle of the city.

This now-defunct synthetic fuel plant was once a major cog in the Nazi war machine.

Disturbing works of outsider art, carved from whole logs.

People in Poland have rallied to save this unnatural desert from being reclaimed by the forest.

Hundreds of notes give thanks to the patron saint of lost causes.

Relive a Polish uprising via an enormous, century-old cyclorama.

Dubbed "Wistom" by locals, this abandoned factory is an urban explorer's dream.

In northeastern Poland, the ruins of a massive granary overlook the Narew River.

An abandoned football stadium with a tragic past.

An abandoned Jewish sanatorium is tucked within the woods of Poland.

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

The final resting place of more than 200,000 people, this is one of the largest cemeteries in Europe.

A World War II torpedo launch station abandoned off the Polish coast.

Memorial to the lost dead of Gdansk, whose resting places were destroyed during World War II.

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

A menacing statue of this mythical creature can be seen at the legendary site of the monster's lair.

Polish luminaries and masterful folk art find sanctuary in this unique cemetery.

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

A mysterious structure left behind on the Polish mountainside, sometimes called "Hitler's Stonehenge".

An abandoned Nazi explosives plant founded by the inventor of dynamite is now an underground museum.

Poland's oldest surviving university building holds a wealth of historic science instruments including some used by Copernicus.