Crystal Lake is located in Mchenry County, IL. The population is 40,269, making Crystal Lake the largest city in Mchenry County.
There are 17 public schools in Crystal Lake with an average Homefacts rating of A-. The total crime rate for Crystal Lake is very low , and there are 53 registered sex offenders residing in the city. Unemployment in Crystal Lake is moderate and the median home sales price is $0. Detailed and up-to-date Crystal Lake property reports are available for any property address.