Drive Highway 130 to the Lake Marie West Trailhead (see Getting There). To find the trailhead from here, follow the highway (or with snow-coverage walk along Lake Marie) until you reach Mirror Lake Campground (as seen on this TOPOZONE). On the link, the center of the map marks the start.
Continue along the trail labeled "Lakes Trail" to to west slopes of Sugarloaf Mountain. From here, leave the trail and scramble the boulders to the top. Descend your ascent route.
The trail will have very little elevation gain, but once you reach Sugarloaf Mountain, the trail will be steep. Also, beware of falling rocks on the mountain; its steep and loose. If you stashed a car (or desire to camp) at Lewis or Libby Lake, just continue out via the trail seen on TOPOZONE or via the Lewis Lake Trail.
General hiking boots, water, and proper clothing is sufficient for summer hiking. Trekking poles make things easier, too. For winter, crampons and/or snowshoes, ice axe, and warm clothing is essential for the steep climb.
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