A fairytale Gothic castle steeped in Nazi treasure conspiracy theories.

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

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

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

An underground city of salt.

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

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

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

A striking public sculpture representing the period of martial law in Communist Poland.

The silly symbol for an underground protest group is now scattered around the city.

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

This magnificent Crimean estate was once a playground of the Russian elite.

One of the cave cities of Crimea, built by the Goths in the sixth century.

A castle perched precariously over the Crimean Sea.

This still-celebrated home was a radical architectural experiment in 3D De Stijl.

This former KGB building is now a museum memorializing the people who suffered during the Soviet regime.

Legend has it that Napoleon Bonaparte fell in love with this Gothic church.

Travelers who fall victim to this mermaid's charms are destined to stay in Užupis forever.

This micro-nation may be some sort of prank, but its constitution sure seems official.

Tables of secondhand books fill the inner courtyard of this 17th-century stock exchange.

This triumphal arch celebrating the Sun King's conquest of Lille is a masterpiece of military architecture.

This unique Lady Liberty is one of the only examples of the figure sitting down.

This 1000 year old relic-filled cave monastery and UNESCO World Heritage Site also hosts an amazing micro-miniature museum.

This 13th century Gothic brick castle is the largest in the world by surface area.