McHenry is a city in McHenry County, Illinois, United States. The 2010 U.S. census reported its population at 26,992 and rests at an elevation of 797 feet. 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, a prominent officer in the Black Hawk War.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 natural features.
In the 1830s various settlers arrived in the area and created the foundation for McHenry. Some of the family names can still be seen today: McCullom, McLean, Boone, and Wheeler.George Gage came to the area in 1835 and purchased a plot of land west of the Fox River. This area eventually came to be known as Gagetown. In 1854, George Gage played an instrumental role in bringing the railroad to the city. Gagetown was eventually renamed to West McHenry.In 1851, a dam was built on Boone Creek which created Mill Pond. The pond encompassed an area between today’s rail road tracks and Route 31 and north of Waukegan Road.
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