Aptly named along the Walnut River at the state park’s southwestern corner, this campground seems like a world of its own. Tall trees form an umbrella over much of the road system and camping spots. Cabins are available in Walnut River Campground, but reservations are highly recommended. The campground has access to a variety of hiking trails, from short and ADA accessible to the 22-mile Boulder Bluff Trail. The area has a nice swimming beach, and a secluded area that’s stocked with rainbow trout November-March.