This is a beautiful walk and if you stay on the main path it's only 1/3 mile. You get a great view on the well and while you're there be sure to look for the small cliff dwillings on the edges of the well.
The last time I was there my daughter was just over a year old and I wore her in a sling with no problem. We stayed mostly on the main path but did take a little side trip on some of the lesser paths and it was I still felt like there was enough footing for that. While on the main path she loved the free run of the place and had a ball out in the fresh air. I really can't wait till she's a little older an is able to spot the cliff dwillings and we can talk about the history of the area. For now she was happy with the ducks and birds she found!