I grew up near Glacier Park and I've spent time in both Yellowstone and Glacier. Hands down, Glacier is place to visit. The park is best experienced outside of your car on a day hike or an overnight trip. The scenery of Glacier Park rivals the Yosemity valley. An awesome day hike is to climb Mt. Siyeh. At the top you can look over the edge of this 4000ft. cliff.