Perfectly preserved ancient monastery in an impossibly dramatic location on a rocky island in the Atlantic.

The ancient tomb acts as a calendar that keeps perfect time.

Gargantuan home of Russian science.

A city block packed with whimsical sculptures that seem to be plucked from a tiled fantasy world.

Museum design and public transportation meet in this unique Russian train car.

The oldest museum in Russia is home to a fascinating collection of nearly two million anthropological artifacts and anatomical curiosities.

A 250-year-old timepiece-automaton adorned with golden mechanical birds, which still sing to this day.

"There's nothing there," and other lies the KGB told us.

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

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

Place with alleged mystical powers in Old Orthodox Church in Sarajevo.

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

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 cemetery was inaccessible for several years due to dozens of land mines.

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

The place where World War I began.

A war-torn Olympic relic is being overtaken by graffiti and nature.

The yawning maw of this pagan visage is said to bite off the hands of liars.

Rome’s legendary peephole vista is also a former Crusader stronghold.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

Whisper secrets in a busy station only to be heard on the other side of this acoustic arch.

A moving memorial to the fallen and missing from WWI trenches.

An underground city of ancient quarry tunnels hid thousands of Allied soldiers in WWI.

The foundations of a forgotten fortress, wedged in between two streams.