McHenry is a city in McHenry County, Illinois, United States. It is located about 46 miles northwest of Chicago. Per the 2020 census, the population was 27,135. 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 the county, which was named for Major William McHenry, a prominent US Army officer in the Black Hawk War.
It rests at an elevation of 797 feet and the Fox River flows through the eastern portion of the city. It 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, Glacial Park Conservation Area, and Volo Bog State Natural Area preserve some of these natural features.
History
19th century
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.
In 1860, the historical Count's House was completed.
On August 4, 1875, the first issue of the city newspaper, the McHenry Plaindealer, was published by Jay Van Slyke.
In 1880, the first bridge in McHenry was built at Pearl Street.
20th century
On March 30, 1908, a train bound for Ringwood crashed near the McHenry train depot. One person was killed.
In 1929, Mill Pond was drained by removing the dam on Boone Creek.
The original single lane Pearl Street bridge was built 1880–1881 over Fox River. The iron truss bridge was dismantled and a section of it was relocated to Terra Cotta Industries in Crystal Lake in Nov. 1976 to be used as a pedestrian bridge. Other sections remain in storage. The original bridge was replaced with a concrete bridge.
In 1985, the McHenry Plaindealer newspaper became part of the Northwest Herald.
Geography
McHenry is located 46 miles northwest of Chicago in northeastern Illinois on the Fox River. According to the 2020 census, McHenry has a total area of McHenry lies within the Fox River Valley, and its downtown area is situated on that river. "The Heart of the Fox River" is the city's motto.
The 48 acre Lake Defiance is the centerpiece of Moraine Hills State Park on the east end of town. It is a glacial lake surrounded by now wooded kames and moraines.
Climate
Typically climate and weather in McHenry year-round is similar to Chicago's, though sometimes it is warmer in summer, and colder in winter. The all-time record high temperature is , set on July 4, 1974, while the all-time record low is , set on January 31, 2019.