We went up here for sunset. We stayed for about a half hour. It was absolutely stunning and so relaxing to see the colors change in the sky and the colors of the scenery change. Definitely recommend!

I would consider Glacier Point to be a "must do" if visiting Yosemite. The sun is best early in the day (we were there at 9AM or so) and before the crowds arrive and the parking lots fill up. We spent 30-40 minutes there but I'd think 90 minutes might be a better time commitment. There are short hiking trails and many spots to just sit and drink-in the marvelous views of Yosemite's mountains and the valley far below.

If one cannot climb the famed Half-Dome in Yosemite, then they ought to do the Glacier Point viewing area. This is a short walk from the car-park and gives amazing views of the Yosemite Valley, Half-Dome and Bridalveil Falls. It's just a photographer's delight. Would highly recommend this spot during sunset. Carry a jacket even in June as people from warmer climates not used to the cold can get a bit cold.