Kusawa Lake sits at an elevation of 671 m (2,201 ft) in the southern Yukon, approximately 60 km southwest of Whitehorse near the British Columbia border. The name derives from the Tlingit word meaning "long narrow lake," which accurately describes its geography: the lake stretches 75 km in length with a maximum width of only about 2.5 km, winding through the mountains of the northern Boundary Ranges. It covers an area of 142 km² and reaches a maximum depth of 140 m, with glacial origins accounting for its notably clear, vividly colored water. The lake is fed by the Primrose River and Kusawa River, and drains northward via the Takhini River.

Access is via an unpaved road branching from the Alaska Highway, roughly 20 km north of the lake. There are two Yukon government campgrounds along this road: a smaller 13-site campground near the Takhini River at approximately Km 15, and the main Kusawa Lake Campground at Km 24. The main campground includes a boat launch, docks, outhouses, bear-proof garbage bins, picnic tables, cook shelters, fire rings, and wheelchair-accessible facilities. The road can become muddy and rutted after rain, and high-clearance vehicles may be advisable in wet conditions.

Because the lake is narrow, paddlers should exercise caution in high winds, which can generate significant wave action in the confined channel. The surrounding Ibex Valley is known for abundant wildlife, including moose, bears, and eagles.

The most popular paddling route in the area is the day trip from Kusawa Lake Campground down the Takhini River to Mendenhall Landing, a distance of approximately 20 km. The Takhini is generally straightforward, with clear channels running down the center, though sweepers can occur on the outside of bends and back channels. One notable rapid — colloquially called the "Jaws of Death" — requires scouting; a short portage is available for those who prefer not to run it. Guided trips typically operate from mid-June through mid-September. Depending on water levels, some trips extend from Mendenhall Landing to the Takhini River Bridge.

The campground's proximity to Whitehorse (under two hours) means it sees heavy use on weekends during summer, so arriving early or visiting on weekdays is advisable to secure a campsite.