Beneath Kraków Old Town's main square lies a hologram-filled medieval market vampire graveyard wonderland.

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

Real bones which are said to have belonged to a Polish dragon.

This Polish cave has housed a dragon, a brothel, and an enduring legend.

This man-made mound monument was built out of soil from all across the Polish empire.

There are thousands of tributes and memorials to the King, but none quite like this one in a Kraków city park.

An underground city of salt.

In the midst of a living monument to Soviet social engineering, Polish Catholics built this church by hand.

This sprawling concrete suburb of Kraków was designed by the Soviet Union as the model proletarian city.

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

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

This abandoned mining village was predicted to resist decay longer than any other modern human settlement.

Cold storage for agricultural biodiversity.

In the northernmost city in the world, it's illegal to be buried because it’s too cold for bodies to decompose.

This insurance company building reminds customers that witches, bears, and gnomes are out there, best be insured.

This medieval Estonian tower provides access to a series of tunnels that have been home to soldiers, punks, and fine art.

The ruins of an Estonian prison are drowning in the quarry lake where the convicts were once forced to work.

This disappearing geyser has been attributed to witchcraft, but really it's all about rainfall.

This Latvian shot factory is still used twice a year to manufacture bullets the old-fashioned way.

Built to ward off Napoleon's army, this city-sized abandoned Russian fort is now perfect for urban exploration.

Medical museum that houses most notably the taxidermied remains of Vladimir Demikhov's famous two-headed dog experiment.

These crumbling Latvian forts make for some haunting seaside ruins.

This abandoned secret city is a crumbling wonderland of Soviet ruins.

A small island less than half a mile from Venice is a forbidden island with a dark and twisted past.