Crystal Lake Map
Crystal Lake Information
Crystal Lake
Crystal Lake is a city in McHenry County in the U.S. state of Illinois. Named after a lake 1.6 miles (2.6 km) southwest of the city's downtown, Crystal Lake is 45 miles northwest of Chicago. The population is 40,269 as of the 2020 Census, a 1.2% decrease from 2010. Crystal Lake is the largest city in McHenry County, part of the Chicago metropolitan area.