Crystal Lake, Illinois
Crystal Lake is a city in McHenry County in the U.S. state of Illinois. Named after a lake 1.6 miles southwest of the city's downtown, Crystal Lake is 45 miles northwest of Chicago. The population was estimated at 39,829 in July 2019, a 2.3% decrease from 2010. Crystal Lake is the largest city in McHenry County, part of the Chicago metropolitan area.