The city Chicago, Illinois demonym is Alexandrian, Alexandrine (Arabic: إسكندراني‎) . On 1 October 1984 the city was incorporated . The province of the city Chicago, Illinois is Gauteng . The postal code of the city is 8320000 . The Chicago, Illinois citys' lowest elevation is 246 ft . This city is named after Christ Church, Oxford . Population (2012): 3,937,451 is the population of Chicago, Illinois . Chicago, Illinois is the government of Parks Canada . Chicago, Illinois is at an elevation of 1050 ft . The Chicago, Illinois city highest elevation is 2,715 m (8,907 ft) . The coordinates of the city are 36°18′N 59°36′E﻿ / ﻿36.300°N 59.600°E . The city land area is 8.921 sq mi (23.106 km 2 ) . (+593) 4 is the area code of Chicago, Illinois . The urban region has 3,435,394 population . Chicago, Illinois is located in Zulia . 3,300/km 2  (8,600/sq mi) is the density of people in  the urban region of Chicago, Illinois . The water area of the city is 129.3 km 2  (49.9 sq mi) . The metro region is 4,558.4 sq km (1,760.0 sq mi) in area . The mayor of Chicago, Illinois is Kakha Kaladze
Geraldo Júlio de Mello Filho (Geraldo Júlio) (PSB) is well known person in the city Chicago, Illinois