This Hungarian castle was built out of cardboard and wood until it proved so popular that it got upgraded to stone.

A once-magnificent collegiate church is falling into ruin.

This giant urban staircase was built to keep the city's brave fighting men from getting waylaid in the red light district.

This abandoned Belgian fortress is purposefully being left to nature.

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

France's most famous cemetery, with some of its most curious tombs.

Made up of 3,200 recycled glass bottles, this tree pays homage to Asturia's love of cider.

The closed and crumbling Francoist luxury resort for workers is still full of life—for now.

See replicas of Europe's most famous cave paintings and even some of the animals that feature in the art.

Head to the mountains to catch a glimpse of Spain's endangered subspecies of brown bear.

A prehistoric cave in Spain contains paintings dating back to the Ice Age.

One of Europe's oldest yew trees has lived more than 2,000 years.

A mountain path passes by several sprawling enclosures home to a pair of rescued brown bears.

This Bronze Age man spent millennia buried in a mine, giving his bones an eerie hue.

It's believed these prehistoric individuals were the victims of cannibalism.

The atmospheric ruins of a historic church can be found on a hill above the city of Oviedo.

Two large posteriors in one giant statue.

The much-loved protagonist of famed Argentinian comics can be found sitting on a park bench.

The surviving remnants of a destroyed medieval church now stand in a public park.