McAdams Peak rises 791 feet above sea level and 372 feet above the Illinois River. The Illini Indians once inhabited these hills and the river valley. In 1892, one hundred Indian skeletons were removed from this vicinity by Prof. William McAdams for the Smithsonian Institution. He also obtained artifacts which are now exhibited at the Centennial Building, Springfield, and at the Monticello Seminary, Godfrey. Forty years later, in 1932, his son, John D. McAdams of Alton, was instrumental in acquiring this property for a state park.