Crystal Lake Campground Trailhead Location: Crystal Lake Campground Google Map Link Crystal Lake Campground Trailhead Vicinity Map Parking: Parking may require a National Forest Adventure Pass. View of the parking area at Crystal Lake Campground. Hikes: Crystal Lake CG to Mt. Islip Loop: 7.5 miles, 2,420′ of gain and loss. Crystal Lake CG to Throop Peak and Mt. Hawkins: 11.5 miles, 3,540′ of gain and loss.