Stillwater is located in north central Oklahoma in Payne County (of which it is the county seat) north-northeast of Oklahoma City at the intersection of U.S. Highway 177 and SR 51 about 15 miles east of Interstate 35.
The city is home to Oklahoma State University, the ameteur-level National Wrestling Hall of Fame/Museum, the Oklahoma Museum of Higher Education and "Old Central", Oklahoma's oldest collegiate building. In addition, the Pfeiffer Farm Collection and the Sheear Cultural and Heritage Museum, which has a 4,000-piece button collection on display alongside other pioneer artifacts.
Outdoor recreation can be found at nearby Lake McMurtry and Lake Carl Blackwell just to the west, the Cimarron River to the south and Sooner Lake and the Arkansas River to the north.
The population estimate for July 1, 1998 was 38,765, an increase of 2,089 since 1990.