I have no miniscus in my right knee, and I'm 60 and over-weight The altitude, you'll notice it, but it's all paved, you can roll anywhere if you're in a chair, but walking is easy too. Lots of benches to stop and catch your breath. I wouldn't recommend the trails, but the area where the visitors center is, is great!
The altitude is a challenge. There is one paved hiking trail from the visitor center to an overlook. There are plenty of spots to pull over and look at the canyon. Other hiking trails would be tough due to elevation. The drive from cedar city is stunning.
RxConsult, I am glad you pointed it out. I have had my back broken and put on a lot of weight. I am the one who runs out steam pretty quickly. Becky has it right, there is plenty to see and hike on the paved trail and many spots to view. That said the ground off the paved areas I'd not that bad. Because you live at sea level, it us expected you are going to get tired. Even the most avid hiker feels it if not used to it. So don't be afraid to speak up. It is better to be smart than sorry. It is worth a little humble pie to go. And you will see some amazing views.
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