Roadside Camp On The Green River
This nice little Campground is all first come first served. Sits on the banks on the Green River. There is water, pit toilets, fire Rings, lamp post, and water. The only downside to the campground is it is located right along a fairly busy two lane Highway. However after dark the traffic Falls to almost zero.
The campground is located a dozen miles or so north of Pinedale Wyoming which offers full services. It also provides easy access to the amazing Green River Lakes area. Just across the highway a gravel road parallels the Green River offering about a dozen free riverside campsites. The main road to these is rough but well maintained. However the road to several of the sites are quite narrow and rough and should be scouted if you're pulling a trailer or driving a larger RV.
There is amazing Wildlife viewing right from the campground. On my last visit I saw mule deer, moose, and Antelope right from my campsite.