Jackson Glacier, Alpine glacier in Glacier National Park, Montana, US

Jackson Glacier sits on the northern slopes of Mount Jackson and ranks as the seventh largest in Glacier National Park. The ice field covers a substantial area and remains visible from the scenic highway that crosses the park.

Jackson Glacier was first documented in 1850, when it was still joined to Blackfoot Glacier as a single ice mass covering 1,875 acres. The two separated sometime before 1929, and the name Jackson Glacier only came into use in 1929. Between 1966 and 2005 the glacier lost almost a third of its acreage, measured at 250 acres in 2005.

The name Jackson Glacier only dates from 1929, when the ice that had been known simply as Blackfoot Glacier split into two. Since then the U.S. Geological Survey has monitored Jackson and Blackfoot through its Glacier Monitoring Research program, using remote sensing and repeat photography from fixed points to track changes in mass balance.

The glacier overlook sits along Going-to-the-Sun Road with designated parking areas and shuttle bus stops for convenience. From this viewpoint, you get a clear view of the ice without needing to hike or take detours.

Jackson Glacier is one of the easiest glaciers in the park to see, lying south of the Going-to-the-Sun Road in upper St. Mary Valley. The U.S. Geological Survey monitors it and Blackfoot Glacier with remote sensing and repeat photography, retaking images from identical spots to track changes in the ice.