Sanganois State Fish and Wildlife Area is at the junction of the Sangamon and Illinois rivers in southwestern Mason County, northwestern Cass County and a small portion in Schuyler County. Sanganois is one of the few state-owned refuges and public hunting areas along the Illinois River.
Prior to state acquisition, the lands and waters within Sanganois were owned and operated as private duck clubs. The largest, and the one which the area derives its name, was the Sanganois Gun Club. This club contained 2,700 acres and was purchased in 1948. Other purchases were made in 1957, 1964 and 1970 to bring the total acreage to 10,360, including approximately 1,700 acres of water. The remaining 8,660 acres are comprised of bottomland timber and cropland (650 acres).
Sanganois State Fish and Wildlife Area is a bottomland environment comprised of sloughs, backwater lakes, timbered ponds and bottomland timber comprised of willow, maple and cottonwood. Both the Illinois and Sangamon rivers contribute to the ecology of the area.