Don't overlook The Grand Tetons NP. Great scenery and critter watching too. Gros Ventre campground is a large cg with big sites but only about 35 have electric. There is a dump station and water available. The office people there were the most helpful we have experienced anywhere. Also only 15 - 20 minutes to the town of Jackson which is very interesting. Too far from YNP for day trips but GTNP is good for several days itself. Gardiner Mt. is only 5-10 minutes from the north gate of YNP and has a couple of good commercial cgs.