Land for sale in Sweetwater County recently totaled nearly $20 million and approximately 1,000 acres. Sweetwater County ranks 17th in the Equality State for the combined amount of land currently advertised for sale. Among cities in Sweetwater County with ranches, farms, hunting land and other rural land and acreage for sale, Rock Springs had the most land for sale. Mining and mineral extraction-related services are the main economic drivers in this part of Wyoming. Sweetwater County is the largest county in Wyoming (10,491 square miles). It's located in the Southwest Wyoming region of Wyoming.