Short, easy hike - not much of a workout, they even have steps built into the rock! Cool city views from inside, totally worth exploring even if you aren't a hiker.
In case this helps other visitors from out of the area - getting here was a bit confusing. Our Uber driver dropped us at an intersection, and from the Papago Park trail maps on one side of the intersection we realized the Hole In the Rock was closest to the other side. It might be easiest to find if you Uber to the Phoenix Zoo entrance and walk to the left.