Some of the cities, towns, and places in McHenry County are Alden, Algonquin, Barrington Hills, Belden, Big Foot Prairie, Bull Valley, Burton, Burtons Bridge, Cary, Chemung, Coral, Crystal Lake, Dorr, Dunham, Fox Lake, Fox River Grove, Franklinville, Grafton, Greenwood, Harmony, Hartland, Harvard, Hebron, Holiday Hills, Huntley, Island Lake, Johnsburg, Lake in the Hills, Lakemoor, Lakewood, Lawrence, Marengo, McCullom Lake, McHenry, Nunda, Oakwood Hills, Palm Beach, Pistakee Highlands, Port Barrington, Prairie Grove, Richmond, Ridgefield, Riley, Ringwood, Seneca, Silver Lake, Solon Mills, Spring Grove, Terra Cotta, Trout Valley, Union, Wonder Lake, Woodstock
McHenry County is a county located in the U.S. state of Illinois. According to the 2020 Census, it had a population of 310,229, making it the sixth-most populous county in Illinois. Its county seat is Woodstock. McHenry County is one of the five collar counties of the Chicago-Naperville-Elgin, IL-IN-WI Metropolitan Statistical Area. Long known as a center of recreation along with agriculture in the western portion, it has more recently experienced rapid rates of suburbanization, exurbanization and urbanization, but the western portions of the county remain primarily agricultural and rural.