Climb the Rock of Guatapé

Monasteries atop soaring rock pillars.

Rhyolite mountains streaked orange, green and pink, with a natural hot river to soak in after the walk — the start of the Laugavegur trail.

Flat-topped cliff hanging 604 m over the Lysefjord.

The "river of five colours", turned red by aquatic plants between June and November.

Cloud-forest valley studded with 60-metre wax palms, the world’s tallest.

Rainbow-striped Andean valley of adobe villages in Argentina’s far northwest.

Mineral springs that have petrified into white waterfalls of stone above the Oaxaca valleys, with cliff-edge pools you can swim in.

Wind-carved chalk mushrooms and icebergs of rock glowing at sunset — camp overnight under the Sahara stars.