Sutherland Falls descends in three distinct cascades, each with its own character. The upper tier drops 229 metres from the lip of Lake Quill, the alpine lake that feeds the falls. The middle cascade is the longest at 248 metres, a near-vertical plunge through a granite channel worn smooth by millennia of water. The lower tier, at 103 metres, fans outward as it nears the valley floor, the water losing cohesion and breaking into spray that drifts on the wind before reaching the rocks below. The total vertical drop of 580 metres covers just 480 metres of horizontal distance, giving the falls an average gradient of roughly 56 degrees - steep enough that from certain angles the water appears to fall straight down, and from others it appears to slide along the cliff face like something poured. The combined effect is less a single waterfall than a sequence, each cascade setting up the next, the sound building as you approach from below.

Lake Quill sits in a hanging valley above the falls, invisible from below, its existence unknown to Europeans until 1890. That year, an explorer climbed the cliff face beside the falls to discover what was feeding them. What he found was a small, cold, glacially carved lake perched on a shelf of rock - a reservoir with no obvious inlet, filled by rainfall and snowmelt that drained through a single outlet over the cliff edge. The lake was named for this first European visitor. It remains one of the more dramatic examples of a geographic feature hiding in plain sight: a body of water that produces one of the country's most impressive natural spectacles yet cannot be seen from any trail, any road, or any easily accessible viewpoint. Helicopters occasionally land near it, but most walkers on the Milford Track, passing through the valley below, see only the falls themselves and must take the lake's existence on faith.

Reaching the base of Sutherland Falls requires a 90-minute return walk from Quintin Public Shelter on the Milford Track. The side trip is not part of the official track - it branches off from the main route on the third day, after walkers have crossed McKinnon Pass and begun the long descent toward Milford Sound. The detour follows a rough trail through dense rainforest to a clearing where the falls come into view, and then to a point near the base where the noise is substantial and the air is more water than atmosphere. Not every Milford Track walker makes the side trip. Some are too tired after the pass crossing. Some are deterred by weather. Those who go tend to agree it was worth the extra effort. The falls appeared in the background of Peter Jackson's film The Hobbit: An Unexpected Journey, in the scene where eagles carry the company over the mountains - a fleeting glimpse of a real place that most viewers assumed was computer-generated.