Darien, previously known as Cass, is a city located in DuPage County, Illinois, in the United States. Situated in the southwestern suburbs of Chicago, the city was named after its Connecticut counterpart. Darien can be found just north of I-55 and the historic U.S. Route 66, which is now referred to as Frontage Road. The city’s southern boundary is shared with Waterfall Glen.

A powerful EF3 tornado struck multiple residential areas in Woodridge on June 20, 2021, before moving on to Darien.

Based on the data from the 2021 census gazetteer files, the area of Darien is measured at 6.28 square miles (16.27 km2), with 98.22% being land (6.17 square miles or 15.98 km2) and 1.78% being water (0.11 square miles or 0.28 km2).

According to the 2020 census data, the city had a population of 22,011 individuals living in 8,697 households, which included 6,297 families.

In Darien, Hinsdale Township High School District 86 oversees the operation of Hinsdale South High School. Meanwhile, a portion of Darien’s residents attend Downers Grove South High School. Darien is also home to Eisenhower Junior High School, Cass Junior High School, Lace Elementary School, Mark-DeLay Elementary School, Concord Elementary School, and Elizabeth Ide Elementary School.

Kingswood Academy is a local private school serving students up to eighth grade. Unfortunately, Our Lady of Peace Catholic School ceased operations in 2020 as a result of dwindling student numbers and financial difficulties.

Route 715, which connects Darien to Westmont and beyond, is serviced by Pace buses.

Some individuals who have gained recognition in their respective fields include Rudy Fratto, a purported high-ranking member of the Chicago Outfit, born in 1943; Doug Lussenhop, a musician, video editor, and comedian known for his work with the comedy duo Tim & Eric, born in 1973; Manu Raju, a journalist; and Barbara Alyn Woods, an actress known for her roles in One Tree Hill and Honey, I Shrunk the Kids, born in 1962.