Great hike. There are many switchbacks for the first two thirds of this hike that will really test out your thighs, and much of the trail is rocky with plenty of tree roots to dodge. It's all worth it, though, once you reach the lake. Hiked on a Wednesday, arrived to an empty parking lot at the trailhead at 7am. We took our time on the switchbacks and were at the lake by 9:30-10am. Started to get plenty of people showing up by noon, with the trail practically a downtown Seattle sidewalk worth of foot traffic on the way back down. Arrive early.