Chickasaw National Recreation Area, park (15 sq mi/39 sq km), S Okla., just SW of Sulpher. Mineral springs, including bromide waters, streams, and lakes. Name honors Chickasaw Nation; authorized 1976, after combination of Platt Natl. Park (est. 1906) and Arbuckle Natl. Recreation Area, after creation of Arbuckle Reservoir.