The walk/hike to the dome is a Tuolumne Meadows gem. The hike to the top of the dome is not an easy one up nor is it down on your legs, knees, and cardio. The difficulty is totally dependent on your physical fitness and wellness. I would leave 4 hours for the roundtrip hike. Wow ... what a great panoramic view. If the hike scares you away, I would take a walk in the meadows across from the restaurant and visitor center and take in a more relaxing view of the whole area with Lembert in the foreground. If you got legs, make the hike.
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