Geologically The Pinnacles are formations that are unique to this area because of their pyramid-like structure. The many small geologic microsites that are found in the area consist of small sandstone structures, volcanic intrusive dikes, badland, and windblown type features The Pinnacles are a nesting grounds for the ferruginous hawk Recreation opportunities include hunting, rock hounding, camping and hiking. This is a fee-free site, Some areas are ADA accessible.