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Buffalo County

Buffalo County is named for the wild bison which roamed the prairie region.


Surrounding County Courthouses: 

N – Hyde County and Hand County

E – County

S – Brule County

W – Lyman County
Created:  January 6, 1864                      Map of South Dakota highlighting Buffalo County

County Seat:

Duncan             1871 – 1885

Gann Valley      1885

Buffalo Center  1886 – 1888

Gann Valley      1888 – present


County Courthouse – Gann Valley


Location:   112 Osman Avenue

Built:  1977 – 1978

Style:  Modern

Architect:  Dana, Larson & Roubal

Contractor:  Boldt Construction of Miller


Description:  The building faces west and is a one story buff colored brick and cement block structure. The building is located on spacious landscaped grounds in the center of Gann Valley. The entrance is on the northwest corner. The front is symmetrical with three bays of which the center bay projects. There are few windows in the small building. The roof line is flat. The County Circuit Court courtroom is located on the east side.  The building houses the County Circuit Court of the 1st Judicial Circuit and the County Magistrate Court.


See:  The 1st Judicial Circuit includes Aurora County, Bon Homme CountyBrule CountyCharles Mix County, Clay County, Davison CountyDouglas CountyHanson CountyHutchinson CountyMcCook CountyTurner CountyUnion County and Yankton County.


History:  The county was created in 1862 and Duncan was selected as the county seat. In 1885, the county seat was moved to Gann Valley and then to Buffalo Center in 1886. The county seat returned to Gann Valley in 1888. The first courthouse was a two story wood frame structure designed by Clarence Beelman and built in 1914. The building was demolished and the third and present courthouse was constructed at a cost of $250,000.



County Courthouse – Gann Valley 















County Circuit Court courtroom



Photos taken 2006 and 2016