Iroquois State Wildlife Area is situated in a low glacial outwash plain associated with the Kankakee River Valley that consists of marshland, sand ridges, and dunes. The initial acquisition of land occurred in 1944 for the purpose of protecting the declining prairie chicken population in the State. The prairie chickens did not survive and public hunting became the major use. The State purchased an additional 560 acres in 1984. Known as the Hooper Branch Savanna, 480 acres of this parcel is considered the largest single tract of rare native savanna remaining in Illinois. The total acreage is now 2,480. The area is located two miles north and three miles east of Beaverville, in the extreme northeast corner of Iroquois County, about 80 miles south of Chicago. The majority of the area, 2,000 acres, is managed as a public hunting area. The remainder of the area is a dedicated nature preserve. Nonconsumptive recreation in the form of hiking and nature study is available when the facility is closed to hunting.