This area was created to save the region's koala population.

A tree that defies gravity grows in an ancient ruin.

Ancient snack bar of the Roman Empire re-opened.

This seaside Italian village doesn't just look Escher-esque, it actually inspired the mind-bending artist.

This breathtaking monastery was established by Saint Benedict himself 1,500 years ago.

Italy's third-largest Roman arena gives a peek into the underground operations beneath the ancient spectacles.

A sulfuric hellscape in southern Italy.

Terrifying derelict military hospital once housed a recuperating Hitler.

A state-of-the-art medical facility from the Imperial era is now a derelict ruin.

Berlin's old airport.

Several of these strange cone-shaped bunkers can still be seen around the former Nazi headquarters.

An abandoned train station in Munich constructed for the 1972 Olympic games.

Virgil's many-mouthed gateway to the underworld.

A massive bridge forms part of an aqueduct that was deemed an architectural wonder of its time.

A stairway to heaven, or to nowhere at all.

The history of German architecture is explored across this fairy-scale mini-city.

No need to strap in for a "ride" on this walkable roller coaster.

This "floating railway" is one of the world's oldest monorail systems.

This Hungarian stilt village is built in a lake that never freezes over due to the power plant that that uses it as a cooling pond.

An abandoned cable car station located on the Danube stands like a haunted house above the river.

A Trabant car, a kangaroo statue, and a plethora of plants take over this abandoned-factory-turned-bar.

From Austrians to Nazis to Soviets, this historic Budapest fortress has a history as complex as the city itself.

Sitting beneath an unremarkable residential building is a museum devoted to classic Pinball.

The romantic garden was the epicenter of the Hungarian art scene in the 1880s.