[4] Crystal Lake is the most populous city in McHenry County, part of the Chicago metropolitan area.

In February 1836, the first white settlers, Beman and Polly Crandall and six of their ten children, came from New York State traveling to Crystal Lake in a covered wagon.

At that time, the main business district for the village of Crystal Lake was located on Virginia Street, about one mile (1.6 km) southwest of the railroad station.

The railroad served to connect both the people and industries of Crystal Lake and Dearborn to Chicago and the rest of the country.

European craftsmen were imported to lay parquet floors, fashion archways and carve interior wood work from black walnut trees grown on the property.

Notable wedding guests included Julian Rumsey (mayor of Chicago and Dole's first cousin) and Levi Leiter (first partner with Marshall Field).

The transaction involved nearly a half million dollars and was one of the largest real estate deals handled in the area.

The original Crystal Lake Country Club faltered in the stock market crash of 1929, and Mrs. Ringling, with her group of investors (the Lake Development Company) subdivided much of the large Dole estate into what is known as the Country Club Additions subdivision[8] parts of which are in the neighboring village Lakewood, Illinois.

[8] The American Terra Cotta Tile and Ceramic Company was founded in 1881[9] just north of Crystal Lake, Illinois.

The company fabricated architectural glazed terra cotta that was used on buildings designed by architects Louis Sullivan and Frank Lloyd Wright in the style of the Prairie School.

American Terra Cotta's company records[12][13] show that architectural glazed terra cotta was used on many local buildings including Oak Manufacturing Company, Teckler Building, Cohn Store, Telephone Exchange and Commercial Building, El Tovar Theatre, Crystal Lake Community High School (now Crystal Lake Central High School) and additions, Central School and additions, Pure Oil Research Lab and additions, Sinclair Refining Company Service Station, Warner Building, Citizens State Bank, Garbe Garage, Home State Bank, various Williams Street stores and bakeries, and Martinetti's Restaurant and Motel.

Disaster shelters were set up to house the homeless, and then-governor of Illinois, Otto Kerner, Jr., personally visited the city to view the damage.

[6] Crystal Lake is the city where the tradition of giving gold coins to the Salvation Army anonymously began in 1982.

[30] As the largest city in McHenry County, Crystal Lake contains three high schools and has many separate neighborhoods.

To the southwest of downtown Crystal Lake is the sprawling Four Colonies neighborhood, which covers nearly 2.5 sq mi (6.5 km2).

An important feature of The Villages is Indian Prairie Elementary School, which is built on a large and steep series of hills that is a favorite sledding location during the snowy months.

Wedgewood includes five ponds, and a forest that backs up to Huntley Road, with a paved walking path.

These neighborhoods consist of many older homes built on the lake shore, and vary greatly in size and style.

Due to the lack of the urban heat island effect, Crystal Lake experiences colder nights and lower precipitation than recorded at Chicago.

Extremely cold nights may record temperatures as low as −20 °F (−29 °C) or lower, but this is rare and does not happen each year.

However, it also shares many cultural opportunities with the city of Chicago, and the other large communities which surround it, as they are easily accessible from Crystal Lake, and vice versa.

Crystal Lake is also home to WZSR Star 105.5, owned by Alpha Media, which broadcasts throughout the northwest suburbs and Fox Valley.

In Crystal Lake lies the famed Dole mansion, where visitors can take tours for a small donation.

Also located in the downtown district is the Raue Center for the Arts, which seats 750 and performs plays and hosts concerts throughout the year.

Raue Center has recently transformed itself into a regional destination spot by providing an in house professional theater company, Williams Street Repertory, Jazz Festival launched by Ramsey Lewis and hosting several recent Tony, Grammy, and Academy award winners.

The city council consists of Ellen Brady, Brett Hopkins, Cameron Hubbard, Mandy Montford, Ian Philpot, and Denise Smith.

Prairie Grove Consolidated School District #46 also serves a portion of northeast Crystal Lake.

In response to pressures from the increasing population, Crystal Lake South High School was opened in 1978.

Also located in Crystal Lake is Faith Lutheran High School, which serves the larger McHenry County area.

Also serving Crystal Lake is the Pace Bus system, which is the owned by the Regional Transportation Authority.