Lake O'Hara and Lake Oesa Loop

This loop links Lake O’Hara with high-alpine Lake Oesa on well-built trails, with the option to return via the more exposed Yukness Ledges. Expect a greatest-hits sampler of the basin in a single outing. The loop is about 5.3 miles total, with roughly 1,300 feet of gain, and typically takes 3–5 hours depending on how much you linger at the lakes and viewpoints.

What you’ll see: classic O’Hara scenery—glacial-blue water framed by larch forest and stonework trails, waterfalls (including the Seven Veils Falls area), and a staircase of tarns leading to Lake Oesa, a jade bowl set beneath cliffs. Big-name peaks are your backdrop: Mount Lefroy, Mount Victoria, and the Yukness and Wiwaxy ridges loom over the route. In summer, watch for wildflowers; in late September, the larches glow gold.

The standard way to make this a loop is to ascend to Oesa, then connect across the signed Yukness Ledges alpine route to circle back toward O’Hara (some versions extend toward Hungabee Lake/Opabin Plateau). The ledges are gorgeous but airy—rocky tread, drop-offs, and rougher footing than the main trails. If that’s not your thing, stick to the out-and-back to Oesa; you’ll still get A+ scenery with fewer nerves.

Access is tightly controlled to protect the area. You can’t drive to the lake. Reserve the day-use shuttle well in advance or be ready to hike the 11 km (one-way) access road. A valid park pass is required. Trails are well signed and maintained, but snow can linger into July at higher elevations and mountain weather turns quickly—pack layers, and treat any stream water. Wildlife is part of the charm (and risk): marmots and pikas are common; mountain goats and bears are possible. Carry bear spray and give all animals space.

Best time to hike: mid-July through September for mostly snow-free conditions and reliable access. Late September is a short, spectacular window for golden larches. Even in peak season the trail feels calmer than other Rockies icons thanks to strict limits—but those same limits make reservations competitive. If you’re confident on airy terrain and want extra drama, consider adding more of the Alpine Circuit (e.g., Wiwaxy Gap) on a clear, calm day.