Day two Climb to 7,050-foot Lincoln Pass before descending into Glacier Basin; continue to Sperry Chalet at mile two. Grab a bowl of soup at this mountain refuge ($3, sperrychalet.com) before setting out on the spur trail (.2 mile beyond the dining hall) to the Sperry Glacier Overlook. You’ll gain 1,600 feet over 2.5 miles, climbing through rocky cirques and up a narrow stone staircase to Comeau Pass. See the gleaming Sperry Glacier and the milky, opaline lakes it feeds far below. Then retrace your steps and rejoin Gunsight Pass Trail to descend along clear and cold Sprague Creek to Lake McDonald—and complete a 14-mile day.
PLAN IT Driving From West Glacier, drive 22 miles east on Going-to-the-Sun Rd. to Jackson Overlook. At Lake McDonald Lodge, catch an Orange or Green shuttle, then transfer to the Red Bus at Logan Pass to return to Jackson.