'The Icefield is said to feed up to 80 per cent of Canada's drinking water, ' he says, 'but most of this glacier's volume has been lost since the 1920s.
It's the cue for effusive guide Fridjon Thorleifsson to introduce the surrounding Columbia Icefield, a 77-square-mile web of six silvery tentacles between Jasper and Banff, and the largest ice cap south of the Arctic Circle.