Twilight zone

Mendenhall Glacier, Juneau, Alaska

From a distance, the Mendenhall is like any other glacier – a vast mass of ice drifting in slow motion over land. Up close, however, it tells a different story – of a thin, steady stream of water that ripples through it, creating enormous caves with ice-blue ceilings. You can wander into this frozen cathedral on foot or hop on a kayak to float under the almost 21-kilometre-long glacier, about 20 minutes drive from the Alaskan capital of Juneau.