South Nahanni River

The South Nahanni River winds through the mountains of the Northwest Territories within Nahanni National Park Reserve, a UNESCO World Heritage Site and one of the most storied wilderness river journeys on the planet. Fed by the Mackenzie Mountains, it plunges over Virginia Falls, nearly twice the height of Niagara, before carving through a series of vast limestone canyons.

The whitewater is remote big-volume Class II–IV, with long stretches of powerful current, read-and-run rapids and canyon sections such as Figure Eight, the river's most demanding rapid, set below towering walls. Most of the run is a swift wilderness float rather than continuous whitewater, and parties portage around the great falls. The scale and isolation, not extreme difficulty, define the experience.

The setting is legendary, wrapped in tales of lost gold and mystery: thundering Virginia Falls, the deep Fourth, Third, Second and First canyons, hot springs, tufa mounds and abundant wildlife including bears, moose and Dall sheep. Access is by floatplane only, and the sense of remoteness is total. Floatplanes from Fort Simpson deliver parties to Rabbitkettle or the falls, and the park's limited permits and mandatory registration keep visitor numbers low across the short ice-free window.

The season is the brief northern summer, June through August, when the river is ice-free and the long days allow travel. Trips typically run one to two weeks from Virginia Falls or higher, and all visitors travel with licensed outfitters or as experienced self-supported parties with park permits. Vast, wild and awe-inspiring, the Nahanni is the definitive subarctic river expedition.