Categories: Illinois geography stubs | 1945 establishments | Illinois state parks | Lake County, Illinois | McHenry County, Illinois McHenry County is located in the state of Illinois. ... Official language(s) English Capital Springfield Largest city Chicago Area  Ranked 25th  - Total 57,918 sq mi (149,998 km²)  - Width 210 miles (340 km)  - Length 390 miles (629 km)  - % water 4. ... A county seat is a term for an administrative center for a county, primarily used in the United States. ... Woodstock is a city in McHenry County, Illinois, United States. ... Incorporated Village in 1957. ... Bull Valley is a village located in McHenry County, Illinois. ... Fox Lake is a village located in Lake County and McHenry County, Illinois. ... Greenwood is a village located in McHenry County, Illinois. ... Hebron is a village located in McHenry County, Illinois. ... Holiday Hills is a village located in McHenry County, Illinois. ... Lakemoor is a village in Lake and McHenry County, Illinois. ... Lakewood is a village located in McHenry County, Illinois. ... McCullom Lake is a village located in McHenry County, Illinois. ... Oakwood Hills is a village located in McHenry County, Illinois. ... Pistakee Highlands is a census-designated place located in McHenry County, Illinois. ... Port Barrington is a village located in Lake County, Illinois and McHenry County, Illinois. ... ... Richmond is a village located in McHenry County, Illinois. ... Ringwood is a village located in McHenry County, Illinois. ... Trout Valley is a village located in McHenry County, Illinois. ... Union is a village located in McHenry County, Illinois. ... Wonder Lake is a village located in McHenry County, Illinois. ... Fox River Grove is a village located in Lake County and McHenry County, Illinois. ... Harvard is a city in McHenry County, Illinois, United States. ... Island Lake is a village located in Lake and McHenry County. ... Johnsburg is a village located in McHenry County, Illinois. ... Marengo is a city located in McHenry County, Illinois. ... Spring Grove is a village located in McHenry County, Illinois. ... Wonder Lake is a census-designated place located in McHenry County, Illinois. ... Cary is a village in McHenry County, Illinois, United States. ... Incorporated Village in 1851. ... The Historic Algonquin Village Hall, the hallmark symbol of the village and the centerpiece of its downtown Algonquin is a village located in both Kane and McHenry County, Illinois. ... Incorporated Village in 1952. ... McHenry is a city in McHenry County, Illinois, United States. ... Woodstock is a city in McHenry County, Illinois, United States. ... Crystal Lake is a city located in southeastern McHenry County in northeastern Illinois. ... The only surviving EMD E5 is used regularly on the museums excursion trains, usually pulling the Nebraska Zephyr. ... Lake in the Hills Airport (IATA: 3ck)is located at located at 8407 Pyott Road in Lake in the Hills, Illinois. ... McHenry County College is a community college in Crystal Lake, Illinois. ... The McHenry Dam is the only dam on the Fox River (Illinois, USA) that is serviced by a lock system. ... The Union Pacific/Northwest (UP-NW) is a commuter rail line provided by Metra and operated by the Union Pacific Railroad in Chicago, Illinois and its surrounding suburbs. ... The Woodstock Opera House as it looks today. ...