Sully County is named for General Alfred Sully, who was the builder of Fort Sully.
Surrounding County Courthouses:
N – Dewey County and Potter County
E – Hyde County
S – Hughes County
W – Stanley County and Dewey County
Created: January 8, 1873 
County Seat:
Clffton 1883 – 1884
Onida 1884 – present
County Courthouse – Onida
Location: 700 Ash Avenue / 7th Street
Built: 1912 – 1913
Style: Neo-Classical Revival
Architect: Black Hills Company of Deadwood ( W M Rich )
Contractor: Gray Construction Company of Watertown
Description: The building faces south and is a two story gray colored stone and concrete structure. The building is located on spacious landscaped grounds in the center of Onida. The building has a raised basement. The main facade also features a portico front with a pediment and entablature. “Sully County 1911″ is located in the center of the pediment. Two round Ionic columns with capitals and two square Tuscan columns with capitals on the corner support the pediment. A beltcourse separates the first and second stories. An entablature spans the building with a dentil molding, providing a transition between entablature and cornice. The first story of stone is laid out in a rusticated pattern. On the center of the roof is an open dome with black colored roof and fore-faced clock. Around the roof is a stone balustrade. In the interior, a stairway extends to each floor with a wrought iron balustrade. The County Circuit Court courtroom is located on the east side of the second story. The building houses the County Circuit Court of the 6th Judicial Circuit and the County Magistrate Court.
See: The contractor, Gray Construction Company of Watertown also constructed courthouses in Clark County, Codington County, Douglas County, Edmunds County, Faulk County, Hamlin County, Hyde County and Walworth County.
See: National Register of Historic Places – Sully County Courthouse
See: The 6th Judicial Circuit includes Bennett County, Gregory County, Haakon County, Hughes County, Hyde County, Jackson County, Jones County, Lyman County, Mellette County, Potter County, Stanley County, Todd County and Tripp County.
History: The county was created in 1873 and the first county seat was Clifton selected in 1883 when the county was organized. The county seat was moved to Onida in 1884 and the first courthouse was erected. The second and present courthouse was constructed in 1912 to 1913.
County Courthouse – Onida
County Circuit Court courtroom
Photos taken 2006, 2010 and 2015