National Register Listings in McHenry County, Illinois
Colby-Petersen Farm
Count's House
Covell, Lucein Boneparte, House
Geister, Christian, House
Hibbard, Charles H., House
Memorial Hall
Old McHenry County Courthouse
Palmer, Col. Gustavus A., House
Rogers, Orson, House
Stickney, George, House
Terwilliger House
Woodstock Opera House
Woodstock Square Historic District
Illinois was part of the French colonial empire, and the city of Cahokia, located near present-day Collinsville, was one of the largest pre-Columbian cities in North America. At its peak, around 1250 CE, Cahokia had a population of around 20,000 people.