UPDATE: County Line Campground has grown quite a bit since we first stayed here 5 years ago. We enjoy the quiet atmosphere. It is located just off of I-29 in Summit, South Dakota. It's easy on and off of the interstate. Calling for reservations is a good idea. The folks who check you in have always been nice and helpful. We travel with a 40 ft. 5th wheel and our sites have always accommodated us nicely, I think most sites are pull thrust and we have always had full hook-ups. Our internet works well here, the campground has their internet as well.