The Horton River runs approximately 600 kilometres from Horton Lake, near Great Bear Lake, north to Franklin Bay on the Arctic Ocean, flowing entirely above the Arctic Circle. It is considered the most northerly major river on the Canadian mainland. The full route takes between 21 and 26 days depending on conditions and layover days. Access is typically by charter floatplane from Inuvik, NWT, with Norman Wells serving as a rendezvous point for some upper-river trips.

The river divides naturally into upper and lower sections. The upper two-thirds is Class I flatwater, transitioning from boreal taiga and stunted spruce forest into open barrenlands tundra. Beginning around the 280-kilometre mark, three distinct limestone canyons introduce Class II to Class III rapids over roughly 50 kilometres. These canyons feature towers, arches, and steep cliffs that attract nesting Peregrine and Gyrfalcons. Intermediate whitewater skills are sufficient for the canyon section, though expedition-level wilderness experience is essential given the length and complete isolation of the route — there are no settlements, no road access, and no reliable communication without a satellite device.

Water clarity is exceptional through the upper river and canyon sections, with visibility to the riverbed. Below the confluence with the West River, approximately 150 kilometres from the coast, the water turns silty. The Smoking Hills region near the coast, a roughly 5,000-square-kilometre area of naturally occurring geological activity where lignite shale and magnesium cause the ground to smoulder, has been found to measurably reduce water quality in the lower Horton. Some outfitters have discontinued travel to the coast for this reason, ending trips before the river reaches the West River confluence.

Wind is the primary hazard on the lower river, where the broad channel can generate large waves capable of pinning parties in camp for days. Firewood in the form of spruce and driftwood is available along most of the route, though a naphtha stove is advisable for the treeless lower section. July is the standard paddling season.

The river corridor supports the Bluenose Caribou herd, muskoxen, grizzly bears, and arctic wolves. Fishing for lake trout, arctic grayling, and arctic char is available. Beluga whales have been observed in Franklin Bay near the river's mouth.