14,100/km 2  (37,000/sq mi) is the density of people in  the urban region of Chicago, Illinois . Alejandro Char  ,  (Radical Change) is the mayor of Chicago, Illinois . On March 6, 1836 (city) the city was incorporated . Chicago, Illinois is at an elevation of 7726 ft .  The city area code is (0)2 . The city is Area: 116 km2 (45 sq mi) in area . The Chicago, Illinois city highest elevation is 424 m (1,391 ft) . The city Chicago, Illinois province is Santiago Province . The city has the postal code 34000 to 34990 . Chicago, Illinois is the government of National Park Service . The population of the metro region is 1,401,687 . The Chicago, Illinois citys' lowest elevation is 7 ft . The water area of the city is 1.63 sq mi (4.23 km 2 ) 1.1% . The city Chicago, Illinois demonym is Guayaquilean . Chicago, Illinois is named for Cartagena, Spain . 2,900/km 2  (7,400/sq mi) is the density of residents in Chicago, Illinois . Chicago, Illinois is located in India . The area of the urban region is 1,770 sq mi (4,600 km 2 ) . The land area of the city is 138.75 sq mi (359.36 km 2 )
The zip code of the city Chicago, Illinois is 080020