Chicagoland is an informal name for the greater area surrounding Chicago. It has a population of about 9,443,356 (2005 est.) and an area of about 10,874 mi². It extends over 3 midwest states, and consists of about 12 counties: * Cook County * DuPage County * Grundy County * Kane County * Kankakee County * Lake County * McHenry County * Lake County * Porter County * Kenosha County The term originated in the pages of the Chicago Tribune in the 1900s.