McHenry is a city in McHenry County, Illinois, United States. The 2010 U.S. census reported its population at 26,992. McHenry was at one time the county seat of McHenry County, which once included adjoining Lake County to the east. McHenry took its name from McHenry County, which was named for Major William McHenry, an Indian fighter.
McHenry is surrounded by natural lakes and streams, grassy moraine hills, gravel banks and shallow nutrient-rich peat bogs, remnants of receding glaciers from the last ice age. Moraine Hills State Park and Volo Bog State Natural Area preserve some of these unique natural features.
- McHenry, Illinois on Wikipedia