The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

A 16th-century horror show built in a lovely Italian garden.

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

A wonderfully strange collection of 500+ stuffed frogs doing people things.

A full figure 4th century incorruptible saint lies in a glass coffin in Croatia.

Now abandoned, the world's first torpedo factory is crumbling into the sea.

Formerly Yugoslavia's "forbidden island," this sleepy little city still holds the abandoned remains of military strongholds.

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

The now-overgrown beach resort was once frequented by Yugoslav military elite.

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

This former estate of a fascist leader is now a burnt out ruin leading to a system of secret tunnels.

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

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

This Croatian island is for sale but no one is buying due to the dozens of accused Nazi sympathizers who were massacred there after WWII.

One of the best-preserved Roman amphitheaters is still used today, but for less brutal events.

When a supermarket opened up shop within a medieval building it became protected by UNESCO on a technicality.

The only gulag ever to exist in socialist Yugoslavia.

When Croatia became independent of Yugoslavia, the splintering governments left behind these concrete tunnels.

A wunderkammer of gold and silver reliquaries and ancient saintly bones.

This picturesque medieval monastery guards a small trove of historic treasures.

Longest fortress system anywhere in Europe.

This huge metal monument is slowly being stripped to its concrete skeleton.

Once a state-of-the-art tuberculosis treatment spa, these ruins are now ruled by paintball players.

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