Scenic helicopter flight over both glaciers and the Southern Alps

Kayak on Lake Mapourika with mirror reflections of the mountains (half-day from $95 NZD)

See glow worms on the Terrace Walk at dusk (free, Franz Josef)

Heli-hike onto Franz Josef or Fox Glacier (3-4 hours including helicopter flight; from $400-450 NZD — expensive but unforgettable)

Walk the free Franz Josef Glacier valley walk to the glacier viewpoint (1.5 hours return)