Rob Roy Glacier

Avalanches peel off the glacier face while you watch — visible and audible from the viewpoint below. Rob Roy Glacier hangs over its cliff like a waterfall stopped mid-plunge, calving ice that thunders down among the real waterfalls threading the valley walls.

The Rob Roy track is Mount Aspiring National Park's perfect half-day: from the Raspberry Creek car park — itself earned via the Matukituki Valley's gravel and fords — the route takes the swing bridge over the river and climbs through ancient beech forest loud with birdsong, and emerges at a viewpoint inside a glacial cirque, waterfalls descending on all sides after rain and the hanging ice above cracking off pieces of itself in real time. The walk in crosses a working sheep station, paddocks and farm gates before the park boundary — high-country New Zealand in one three-to-four-hour return. The glacier is retreating, its change legible year on year, which sharpens rather than softens the spectacle.