Longest fortress system anywhere in Europe.

Former military fort and site of untold horrors during WWII, this island may become the Adriatic's next luxury resort.

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.

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

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

Amid the marketing blitz of modern Times Square is an elegant holdover from its showbiz glory days.

This enormous abstract sculpture is part jungle gym, part elaborate noise-making machine.

Ancient Egyptian relief, claimed to depict an electrical light.

This extraordinary geological oddity resembles human-made pavement.

Rare recess caves fill this unbelievably beautiful Ohio park.

The land is full of geologic eye candy, such as otherworldly spires, mushroom-shaped hoodoos, and prehistoric fossils.

This abandoned Olympic skiing facility still bears the scars of the Siege of Sarajevo.

This museum preserves the hand-dug tunnel that kept Sarajevo afloat during the Serbian siege.

A number of craters left by fatal mortar strikes have been filled with red resin to remember those lost during the Siege of Sarajevo.

This historic timepiece is thought to be the only public clock in the world that keeps lunar time.

Oriental bazaar in the heart of Sarajevo.

Inat Kuća, or "House of Spite," is more than just an oddly named restaurant.

Celebrated example of Ottoman architecture that also served as a site for brutal massacres.

A Serbian church lit by chandeliers made of weapons.

A misnamed well, with a deep dark past.

A towering spire in the fortress of Kalemegdan honors the victorious armies of Serbia during their struggles against the Ottoman Empire.

A small memorial to a deadly night in Serbia that shook the world before it was swept under the rug.

A pair of connected skyscrapers form this symbolic gateway.