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

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

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

This uber-quaint Polish village is known for its habit of painting elaborate floral motifs on just about everything.

This Nazi ruin was the site where Hitler was almost blown up by a suitcase bomb.

The site of the first battle of World War II.

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.

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

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

The complex has been abandoned since the Croatian War of Independence, barring a stint as a set for 'Game of Thrones.'

This deserted town in the hills of Croatia’s "party island" may have a scandalous connection to King Henry VIII.

This fountain has a growing (animal) population, and might also be growing in size.

This only museum in the world dedicated solely to mushrooms.

This unique structure allowed boats to bypass underwater mine barriers in the channel to enter the harbor.

This beautiful Croatian fortress is haunted by legends of forbidden love.

A tribute to an iconic act of defiance from the Croatian War of Independence involving a small car.

Just a few miles from Novalja, a strange geological oddity has left scientists baffled.

This 135-year-old weather station studied the effects of the climate on human health.

The oldest arboretum on the Dalmatian coast doubles as the gardens of Kings Landing in "Game of Thrones."

Dive for drinks at Croatia's first and only underwater winery.

This military tunnel dates back to World War II and provides visitors with a little wartime adrenaline.

Croatia's "hairy stone" fortress is one of the most well preserved Istrian castles.

This Croatian fairytale castle is slowly falling apart thanks to years of neglect.