Formed January 1, 1864 (11th county)
Buffalo County (1,945), Gann Valley (10), Fort Thompson (1,224)
The tan brick Modern building was erected in 1979. The facility is at Osman and Main avenues. The location is one block west of South Dakota State Highway 45. Dana, Larson & Roubal designed the courthouse. A Liberty Bell replica sits on the grounds. There was a 1914 wooden building previously. The county was founded on January 1, 1864 as the 11th county. Duncan (1871), Gann Valley (1885 & 1888), and Buffalo Center (1886) have all served as the county seat. Buffalo County is named for the animal. They also inspired the name of the county seats of Harding County and Perkins County. The county seat was named for settler Herst Gann.
Buffalo County government consists of a sheriff and 3 Commissioners. Six Circuit Court Judges and One Magistrate Court Judge serve Buffalo, Aurora, Bon Homme, Brule, Charles Mix, Clay, Davison, Douglas, Hanson, Hutchinson, McCook, Turner, Union and Yankton counties. The county is in south central South Dakota. The Missouri River forms its western border. Pierre, South Dakota is northwest and Sioux Falls, South Dakota is east of the county. The county center is 17.5 miles West-Northwest of Gann Valley nearer Fort Thompson. The county is surrounded clockwise by Hand, Jerauld, Brule, Lyman, and Hyde counties.
The area of the county is 471 square miles. It is 61 out of 66 in the state. It ranks 58 out of 66 in population in the state. It has a density of 4.1 persons per square mile making it 38 out of 66 in the state. Buffalo County has 0.0% of its population in its incorporated areas since there are no incorporated cities. There are no Interstates or United States Highways in the county. The county shape looks like a teapot without the top. Gann Valley is located in the southeast quarter of the county. Fort Thompson is on the western border of the county. Gann Valley is the county seat and Fort Thompson is the largest populated area. Gann Valley is 0.5% of the county population while Fort Thompson is 62.9% of the county population.
Gannvalley (unincorporated)
