Spain's Aragon region isn't exactly famous for its forests—it's more 'sun and scrub' than 'shade and shuffle.'

And yet, climb the slopes of Moncayo and you'll walk straight into a twist ending: a dense, whispering beech forest.

The mountain is a climate roller coaster.

At the bottom? Mediterranean shrubs.

Midway up? Oaks and pines.

Push further? Suddenly you're in Peña Roya, a beech wonderland that seems to say, 'Surprise, leaf it to me!'