I vote as well for Blue Mountain in Blanding. Over the last ten years, I probably spent three months or better there. Still haven't hiked all the canyons. If you are a hikers look up Cedar Mesa just east of Blanding on the way to Natural Bridges. Amazing Anaszi cliff dwellings. Some are easy to get to and other are only for experienced canyon rats like us.
Don't miss Twin Rocks Trading Post and café in Bluff.
The maintenance guy, Gary, knows every nook and cranny in the area and will gladly help you with directions.
Ditto on the Edge of Cedars Museum. Well worth the admission fee.