The 525-acre McKinley Woods was acquired between 1931 and 2004. The preserve is part of the Des Plaines River preservation system, which conserves more than 2,400 acres of land. Prior to the District's acquisition of the land, it was used as a Civilian Conservation Corps camp, and the Frederick's Grove Shelter is a remnant of that camp. Frederick's Grove is one of two access areas to the preserve. The other access area is Kerry Sheridan Grove in Channahon.