Three Isle Lake Trail

Start at the kiosk at the north end of North Interlakes Day Use Area. The route follows an old, rocky road beneath steep slopes, with Upper Kananaskis Lake on your left as you head west. At about 0.9 km, the northern side of the Upper Lake Circuit branches off; another connector joins around 2.2 km. Stay on the route toward Three Isle rather than turning onto the full lake circuit. The Palliser rockslide is a landmark on this stretch. Invincible Creek, about 3.8 km from the start, marks the end of the bike-permitted section. Beyond it, the tread narrows and continues on foot through older forest.

The forested path leaves the lakeshore and follows the Kananaskis valley toward Forks Backcountry Campground, near the meeting of the Upper Kananaskis River and Three Isle Creek. Expect a quieter stretch under trees before the route reaches the open campground area. Forks is a useful place to stop, check your pace and eat before the final climb, but it is not the destination. There is no food service along the trail, so carry enough for the full day or overnight.

Past Forks, the trail rises gently at first, then climbs sharply up the headwall. A stream crossing and steps break up the ascent, but this is still demanding after the long approach. Slow down and take breaks before you are tired. Near the top, the route drops roughly 30 m to a signed junction: take the left branch for Three Isle Lake; the campground is to the right.

Mount Worthington rises above the lake and its rocky shoreline. Leave time to pause before retracing the route. For a photograph, frame some of the stony shore in the foreground with the mountain above it. The backcountry campground has two separate loops about half a kilometre apart; both are overnight facilities rather than day-use areas.

North Interlakes has pit toilets, but there is no food vendor on the route. Lake and creek water is untreated, so bring what you need and treat any water collected. The Three Isle campground has toilets and secure food storage, prohibits fires, and requires a reservation for overnight stays; the campground operates seasonally. Alberta park rules allow dogs on leash no longer than 2 m. The group-size limit is 15. Start early, carry enough food and water for a full day, and leave room in your schedule for the headwall and return walk.