We’re very familiar with twin knobs. Zilpo is the backwoods cousin. A bit more remote, but we found the campground to be fantastic. It is more densely wooded than twin knobs. The sites are generally just as good, but there is more variety between primitive/hookup/cabins. The beach is not quite as big, but plenty big, and wasn’t crowded over July 4 weekend. The beach store has bare essentials. There doesn’t seem to be ranger programming. Not all the loops have showers in the bathroom buildings.
RV park in the front, more primitive tent camping in the back. There is a pond/lake just big enough to fish and swim in, and there’s a rope swing the kids loved. This place has pretty good food made on site and had karaoke on Saturday nite with a good crowd. The spots were good, if not a bit close together. We didn’t have a picnic table but we brought a table so it wasn’t a big deal for us. Also I think they would get you one if you didn’t have one. Staff was great. Fire pit was Flinstone style: just a ring of rocks. But it got the job done. Very close to Slade and Stanton.
Twin Knobs is a great campground with many different loops of spots, electric and non, and many amenities. Basketball, volleyball, bathrooms, amphitheater, beach, and more. Many sites are either close to the water or a quick walk. You can park your boat in coves and tie off near your site.