Jackson Glacier Trail

Jackson Glacier Trail is a 1.1-mile point-to-point spur from Gunsight Pass Trail to a glacier-fed stream beneath Jackson Glacier, with about 630 feet of climbing. That distance is one way for the named branch. Its junction is roughly six miles along Gunsight Pass Trail from Jackson Glacier Overlook, so hiking from the road, doing the spur and returning is about 14–15 miles. Allow about 1½ hours for the spur itself and set aside a full day for the whole outing. This is the close-up option for the glacier basin; the roadside overlook gives you a glacier view without the long approach.

The first 0.15 mile is level, then the route climbs steeply for about a quarter-mile over loose, rough tread. There are a couple of short places where you may want a hand for balance. Take this section slowly: once you reach the ridge, the trees thin and the trail crosses open alpine meadows kept wet by meltwater. The climb eases, but the ground can stay soggy.

The trail finishes at a larger stream draining from the glacier. Jackson Glacier sits higher on the slope beyond broad rock slabs; the route does not continue across the moraine. Turn back at the stream and return on the spur to the Gunsight Pass Trail. For a photo, keep some of the wet meadow or stream in the foreground with the glacier above it; that shows the setting without implying you can hike to the ice.

The view is a chance to see what remains of a named glacier in a warming mountain range. The park measured Jackson Glacier at 316 acres in 1966 and 187 acres in 2015. Historic and repeat photographs document substantial retreat over the twentieth century; comparisons from 2009 and 2020 showed little apparent change in its visible extent over that shorter period.

Start at Jackson Glacier Overlook on Going-to-the-Sun Road, then follow Gunsight Pass Trail about six miles to the branch just south of the St. Mary River bridge. The overlook has parking and a shuttle stop; there is no direct road access to the spur. Dogs are not permitted on park trails. In autumn, snow can return and most seasonal bridges are removed by late September, so check the current trail status before committing to the long approach.