This is a favorite campground for fishermen (though we are not). Henry's Lake is serene and beautiful. The small park is far enough from the highway that it is quiet. There are several lakeside sites, though all of the sites have a lake view of some kind. This is one of those "nothing fancy" campgrounds that's just nice to be in.
This is not what we expected of a KOA. We had made online reservations knowing we would arrive after hours. We were not assigned a site. Instead, in the dark, in an unfamiliar campground, we were to choose an empty space. It was very frustrating and didn't feel very welcoming. The office wasn't open in the morning (it opened at 1:00!!) so we didn't even get officially checked in until afternoon--which meant we had to make a trip back out to the campground later in the day. The whole campground was quite untidy with litter and branches all about. Our site had piles of red dirt next to where our door was. We wouldn't go back, nor recommend this KOA to friends. Too bad, because RV parks in Sheridan are scarce.