Land for sale in South Dakota's Mellette County recently totaled almost $5 million and almost 2,000 acres. Mellette County ranks 42nd out of 66 counties in the state for the total number of acres of land currently advertised for sale. White River featured the most land for sale. Its economy is defined as agricultural, with 229 farms recorded in the county during the most recent U.S. Census. Farming activities in Mellette County generate annual revenues of $3 million, the majority of which comes from livestock products. Mellette County is the 21st biggest county (1,310 square miles) in South Dakota. It's located in the Black Hills & Badlands South Dakota region of the state.