In a recent trip to Flagstaff, we decided to stop at Wupatki on the way home. What I didn't realize at first was that Sunset Crater Volcano and Wupatki are connected. We did the Sunset Crater national monument first and it was ok. I wasn't sure what to expect from Wupatki National Monument, but when we came upon the first ruin, we were amazed. There are four to five sites to visit. The large one we came upon first was open to climb up through. There is a slight walk from the parking area and would be challenging for anyone with difficulty walking.
The visitor center is very good and we enjoyed reading about all the different elements of the ruins. Be sure to stop in the Visitor's center first. We did not and went right to the ruin behind it. At the visitor's center you can get a booklet that tells you what each of the numbered exhibits are when you're walking around the ruin. We ended up buying one to take with us (you can borrow one for free or buy one for $1). It answered a lot of our questions. Our children 13 and 15 were fascinated with it all. Definitely a great place to stop.