If you have one day to take in the highlights of Glacier National Park, drive Going-to-the-Sun Road (GTSR) in its entirety. GTSR is a 50-mile long, two-way road that cuts through the center of the park between the West Entrance and the St. Mary Entrance. Your journey can begin at either location. To return, either retrace your path back over GTSR, or take U.S. Hwy 2 along the south border of the park to create a loop. Along U.S. Hwy 2, you will find scenic views, some restaurants and lodging.
Stop by a visitor center for trip planning information or to catch a free park shuttle (and leave the driving to someone else!). Though they all contain unique exhibits, you do not necessarily need to visit every visitor center.
With a whole day to enjoy, you can take advantage of the many short hikes accessed from trailheads along GTSR. If you get an early start, you could probably fit in a half-day hike (less than 8 miles, 3-5 hours). Or take at least one of the under 2-mile (3.2 km) hikes.
After a long day of travel (and perhaps some dinner), it is time to take a seat...at a campground amphitheater or an auditorium. Attending a ranger evening program is a great way to finish your day in Glacier.