This remote fort on the Yukon River is a vestige of the wild Alaska gold rush.

This heart-shaped island looks substantially less lovely after a recent bulldozing project.

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

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.

The only gulag ever to exist in socialist Yugoslavia.

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

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

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

The remains of a sunken military ship wreck visible through clear water.

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

This truly palatial work of Communist-era architecture now sits crumbling on a Croatian beach.

Large, airy hallways hide within an impenetrable fortress that beckons urban explorers.

Mysterious painted skulls in Moravia.

The mystery of the Putim Ossuary involves a tricorn hat.

These 17th-century mummies are no longer naturally preserved, but remain on display today.

Folklore says this medieval fortress was plopped atop a portal to hell to trap the demons below.

Bullet holes in the church wall are a reminder of the violence that followed the assassination of a high-ranking Nazi officer.

Mummified monks and the accidentally interred, in a 17th-century crypt.

Europe's second largest ossuary wasn't discovered until 2001.

Underneath this small church are 15,000 bones, arranged by an obsessive academic.

What looks like a suicide in progress is actually a statue of Sigmund Freud.

This oddly named town refuses to change its phallic moniker.

Smallest house in Toronto sits on a lot meant to be just wide enough for cars to drive through.

The childhood home of Henry Jones Jr. is now an adventure-themed bed and breakfast.