Roads and expressways in Chicago

Chicago's streets were laid out in a grid that grew from the city's original townsite plan platted by James Thompson. Streets following the Public Land Survey System section lines later became arterial streets in outlying sections. As new additions to the city were platted, city ordinance required them to be laid out with eight streets to the mile in one direction and 16 in the other direction. A scattering of diagonal streets, many of them originally Native American trails, also cross the city. Many additional diagonal streets were recommended in the Plan of Chicago, but only the extension of Ogden Avenue was ever constructed. In the 1950s and 1960s, a network of superhighways was built radiating from the city center.[1]

As the city grew and annexed adjacent towns, problems arose with duplicate street names and a confusing numbering system based on the Chicago River. On June 22, 1908, the city council adopted a system proposed by Edward P. Brennan;[2] amended June 21, 1909. The changes were effective September 1, 1909 for most of the city.[3]

Addresses in Chicago and some suburbs are numbered outward from baselines at State Street, which runs north and south, and Madison Street, which runs east and west.

The division of Chicago's directional address system is at State Street - separating East (E) from West (W), and Madison Street - North (N) from South (S).

A book was published in 1909 by The Chicago Directory Company indexing the old and new street numbers for most of Chicago. This volume is available online in PDF format indexed by initial letter, Plan of Re-Numbering, City of Chicago, August 1909.[3] The opening text of the book says: EXPLANATORY

The new house numbering plan passed by the City Council June 22, 1908, to be in force and effect September 1, 1909, makes Madison Street from Lake Michigan to the city limits on the west the base line for numbering all north and south streets and streets running in northerly or southerly direction. For east and west streets and streets running in a generally east and west direction the base line is State Street from the southern city boundary line to North Avenue, thence extended by an imaginary line through Lincoln Park and Lake Michigan.

The downtown area did not conform to this system until April 1, 1911, per an amendment to the law on June 20, 1910. Downtown was defined as Lake Michigan on the east, Roosevelt Road (Twelfth Street) on the south, and the Chicago River on the north and west. The addition to cover downtown was published, and is also on line as a pdf indexed by downtown street name.[4]

This additional paragraph explained the downtown changes:

The 1909 address change did not affect downtown Chicago, between the river and Roosevelt Road, the river and Lake Michigan. The ordinance was amended June 20, 1910 to include the downtown area. The new addresses for the “loop” went into use on April 1, 1911.

Chicago house numbers are generally assigned at the rate of 800 to a mile. The only exceptions are from Madison to 31st Street, just south of downtown. Roosevelt Road (previously Twelfth St) is one mile south of Madison with 1200 addresses to the mile, Cermak Road (previously 22nd Street) is two miles south of Madison with 1000 addresses to the mile, and 31st Street (3100 S) is three miles south of Madison with 900 addresses to the mile.[3] South of 31st Street, the pattern of 800 to the mile resumes, with 39th Street the next major street, 47th after that, and so on. Individual house numbers are normally assigned at the rate of one per 20 feet of frontage. Thus the last two digits of house numbers generally go only as high as 67 before the next block number is reached. Higher house numbers are found on diagonal streets and have sometimes been assigned by request.

The blocks are normally counted out by "hundreds," so that Chicagoans routinely give directions by saying things such as "about twelve hundred north on Western" or "around twenty-four hundred west on Division" (which both describe the intersection of Western Avenue (2400 W) and Division Street (1200 N)).

South of Madison Street most of the east–west streets are simply numbered. The street numbering is aligned with the house numbering, so that 95th Street is exactly 9500 South. "Half-block" east–west thoroughfares in this area are numbered and called places; 95th Place would lie just south of and parallel to 95th Street, and just north of 96th Street.

Every four blocks (half-mile) is a major secondary street. For example, Division Street (1200 N) is less important than either Chicago Avenue (800 N) or North Avenue (1600 N), but is still a major thoroughfare. However, this is not always the case; for example, on the city's Far North Side, Peterson Avenue (6000 N) is a more heavily trafficked street than Bryn Mawr Avenue (5600 N), which sits exactly at the 7-mile marker. U.S. Route 14 is routed along Peterson between Clark Street at 1600 W and Cicero Avenue at 4800 W, whereas Bryn Mawr is discontinuous, split into two segments in this part of the city by Rosehill Cemetery between Damen and Western Avenues.

Even-numbered addresses are found on the north and west sides of a street, and odd numbers are found on the south and east sides, irrespective of the streets' position relative to the corner of State and Madison.

Diagonals, even if they were to run exactly 45 degrees off of the cardinal directions, are numbered as if they were north–south or east–west streets. Examples are North Lincoln Avenue and Ogden Avenue, which bends at Madison and changes from North Ogden to West Ogden.

The northernmost street in Chicago is Juneway Terrace (7800 N), just north of Howard Street. The southern boundary is 138th Street. The eastern boundary of Chicago is Avenue A/State Line Road (4100 E) along and south of 106th Street, and the furthest west the city extends is in the portion of O'Hare International Airport that lies in DuPage County, just east of Elmhurst/York Road.

While all north–south streets within city limits are named, rather than numbered, smaller streets in some areas are named in groups all starting with the same letter; thus, when traveling westward on a Chicago street, starting just past Pulaski Road (4000 W), one will cross a mile-long stretch of streets which have names starting with the letter K (From east to west: Keystone (North Side)/Komensky (South Side), Karlov, Kedvale, Keeler, Kildare, Kolin, Kostner, Kenneth, Kilbourn, Kolmar, Kenton, Knox, Kilpatrick, Keating), giving rise to the expression "K-town". These streets are found approximately in the 11th mile west of the Indiana state line, and so begin with the 11th letter of the alphabet. A mile later, just past Cicero (4800 W), the starting letter changes to L, and mile by mile the letters progress up to P. Additionally, for most of the first mile west of the Illinois/Indiana state line, streets are lettered from Avenue A at the state line (4100 E) to Avenue O (3430 E), forming the A group. The areas that might otherwise be the B through J groups are the older parts of the city where street names were already well established before this system was developed (although some small groups of streets seem to have been given names intended to conform to the system), and the Q group (8800 to 9600 W) would fall west of the city, as the only land in Chicago west of 8800 West is O'Hare International Airport, undeveloped forest preserve, and a small strip of land connecting O'Hare to the rest of the city and containing only Foster Avenue.

Some suburbs number their east–west streets in a continuation of the Chicago pattern, and even more number their houses according to the Chicago grid. A few suburbs also number their north–south avenues according to the Chicago grid, although such numbering vanished from Chicago itself long ago (the alphabetical naming scheme was devised to help eliminate it). For example, the 54th/Cermak terminus of the Pink Line is located near the intersection of 54th Avenue and Cermak Road (22nd Street) in Cicero. This is 54 blocks west of State Street in Chicago. A minor street 54+1⁄2 blocks west of State Street would be called 54th Court (in reality, that is Lotus Avenue in Chicago).

This pattern continues as far west as Plainfield, which has a 252nd Avenue, as far north as Skokie at Central Street (10100 North),[5] and as far south as the southern edge of Will County. Suburbs that follow the Chicago numbering system include Niles, Rosemont, Morton Grove, Skokie, Lincolnwood, Franklin Park, River Grove, Evergreen Park, Oak Lawn, Oak Forest, Matteson, Channahon, unincorporated parts of Des Plaines, Glenview, and other parts of Cook County, Will, and DuPage Counties. Other suburbs, including Evanston, Park Ridge, Oak Park, Glenview and Wilmette use their own numbering systems. The six "collar" counties (DuPage, Kane, Kendall, Lake, McHenry, and Will) use State and Madison as a base line. For example, 32W000 in DuPage County is 32 miles west of State Street, 38000 in Lake County would be 38 miles north of Madison Street, and is normally used without the direction letter. In these counties, unlike Chicago, numbering is 1,000 numbers to the mile, so in DuPage County 32+1⁄2 miles west is 32W500.

Some Chicago suburbs in adjoining Northwest Indiana also use the Chicago numbering system. These include East Chicago, Whiting, and Hammond. There are even examples further south in Lake County in Dyer and Schererville such as 205th Place through 215th Street (these examples coordinate with the Chicago grid, not the Gary street system). Other municipalities, such as Highland, and Griffith are based on the Gary, Indiana numbering system, beginning with 5th Avenue in Gary and increasing numerically as one travels southward. Examples in Scheider in the far south of Lake County, Indiana go as far down as 244th Avenue.

The aforementioned pattern also occurs in Waukegan, Illinois, with Washington Street being the baseline between north and south. Nearby municipalities such as Gurnee, Park City, and North Chicago continue with the Waukegan numbering pattern, while rural areas in Lake County, Illinois follow the Chicago grid.

The city of Chicago proper contains seven major Interstate highways.[8]

Roadway Name	Numbers	Description
Kennedy Expressway (Northwest Expressway)	I-90 I-94 I-190	Runs from O'Hare east and south to downtown Chicago. It interchanges with the Jane Addams and the Tri-State Tollways near Cumberland Avenue on the city's far northwest side, with the Edens Expressway near Montrose Avenue on the near northwest side, and with the Dan Ryan and Eisenhower Expressways at its southern terminus downtown at the Jane Byrne Interchange. The portion from O'Hare to the Jane Addams and the Tri-State Tollways is I-190; the remainder is signed as I-90. I-94 is overlaid on I-90 south of the junction with the Edens.
Jane Addams Memorial Tollway (Northwest Tollway)	I-90 Toll	Runs from its complex interchange with the Kennedy Expressway and the Tri-State Tollway through the northwest suburbs towards Rockford and South Beloit.
Edens Expressway	I-94 US 41	Runs south from Park Avenue West in Highland Park to its interchange with the Kennedy Expressway near Montrose. The Edens Spur (formally a part of the Tri-State Tollway) splits off at the north end to interchange with the mainline Tri-State. All of the Edens south of the Edens Spur is signed as I-94; the 4-mile (6.4 km) northernmost section is signed as US 41 from the Edens Spur to the Skokie Road exit in Wilmette. US 41 continues north as Skokie Highway beyond the northern terminus of the Edens.
Dan Ryan Expressway	I-90 I-94	Runs south from the Jane Byrne Interchange near the Loop to the Bishop Ford Freeway in the Far Southeast Side in Chicago. In between, the Dan Ryan interchanges with the Stevenson Expressway and the Chicago Skyway near 66th Street. The portion between the Jane Byrne Interchange and the junction with the Chicago Skyway is overlaid with I-90.
Eisenhower Expressway (Congress Expressway)	I-290 IL 110 (CKC) IL 53	Runs west from the Jane Byrne Interchange to an interchange with the Tri-State Tollway and the eastern terminus of the Ronald Reagan Memorial Tollway (I-88) near Hillside, Illinois. Further west, I-290 turns northwest and becomes the "Eisenhower Extension". At the interchange with I-90 near Schaumburg, it continues as IL 53 until eventually terminating at Lake Cook Road. East of the Jane Byrne Interchange, the route continues downtown as Ida B. Wells Drive.
Stevenson Expressway (Southwest Expressway)	I-55	Runs southwest from Lake Shore Drive to the Tri-State Tollway in Burr Ridge. Along the way, the expressway interchanges with the Dan Ryan before heading to the south and southwestern neighborhoods of Chicago. The Stevenson then continues past Midway Airport and out of Chicago.
Veterans Memorial Tollway (North–South Tollway)	I-355 Toll	Runs south from an interchange with I-290 near Itasca to I-80 near New Lenox. Along the way, I-355 runs through the western suburbs to an interchange with I-88 before continuing south to the interchange with I-55. Then it continues south along 11 miles (18 km) of tollway to its southern terminus at I-80.
Ronald Reagan Memorial Tollway (East–West Tollway)	I-88 Toll IL 56 Toll IL 110 (CKC)	Runs from a complex interchange with the Eisenhower Expressway and the Tri-State Tollway west to U.S. Route 30 near Rock Falls. Along the way, the tollway meets another complex interchange with I-355. Then it heads through the western suburbs into north-central Illinois.
Interstate 57 (Dan Ryan West Leg)	I-57	Runs south from the junction of the Dan Ryan Expressway and Bishop Ford Freeway to the southern suburbs. Known originally as the "Dan Ryan West Leg", the name has since dropped from common usage. As such, it is the only freeway within the city of Chicago lacking a formal name.
Bishop Ford Freeway (Calumet Expressway)	I-94	Runs from the southern terminus of the Dan Ryan Expressway, heads east, then south through the Far Southeast Side in Chicago to the southern suburbs before ending at a junction with the Kingery Expressway and the Tri-State Tollway. South of that point, it continues as the Calumet Expressway (IL 394).
Chicago Skyway (Calumet Skyway)	I-90 Toll	The Skyway angles off from the Dan Ryan Expressway near 66th Street and heads southeast toward Indiana. The Skyway ends after a toll bridge over the Little Calumet River and the Indiana state line, at which point it becomes the Indiana Toll Road.
Tri-State Tollway	I-80 Toll I-94 Toll I-294 Toll	Serves as a toll bypass around Chicago. The tollway runs from a combination interchange with the Kingery Expressway and the Bishop Ford Freeway towards an interchange with US 41 just south of the Wisconsin state line. North of the junction with the Edens Spur the Tri-State is signed as I-94; on and south of this it is signed as I-294, the southern part of which is overlaid by I-80.
Kingery Expressway	I-80 I-94 US 6	Located entirely in Lansing, Illinois, this is a three-mile-long expressway running from the interchange with the Bishop Ford Freeway and the Tri-State Tollway to the Illinois/Indiana border.
Lake Shore Drive	US 41	A major limited-access highway running along the Lake Michigan shoreline from East 67th Street in southern Chicago to Hollywood Avenue in Chicago's Edgewater neighborhood. For most of its length, Lake Shore Drive is signed as US 41. Portions of Lake Shore Drive were constructed as an expressway.
Elgin Bypass	US 20	A five-mile freeway signed as US 20, bypassing Elgin, Illinois. It goes west from the Villa Street interchange, meets IL 25, crosses the Fox River, then meets State Street, McLean Boulevard, and Randall Road before continuing at-grade.
Kingery Highway	IL 83	From Bensenville, the Kingery Highway heads south 18 miles to just south of the Des Plaines River. It is a multi-lane divided limited-access road with grade-separated portions.[9][10]
Amstutz Expressway	IL 137	A two-mile expressway located entirely in Waukegan, Illinois. It has only one exit at Grand Avenue.
Elgin–O'Hare Tollway ( Elgin–O'Hare Expressway)	IL 390 Toll	Formerly an unnumbered free expressway, it heads west from IL 83 in Bensenville through Itasca, Roselle, and Schaumburg until terminating at an interchange with U.S. Route 20. Until 2017, the expressway ended at IL 53 in Itasca. A one-mile eastern extension to I-490 is under construction.

Cook County has a modest amount of county roads after plans were made in 2009 to designate many roads on county ownership as a public service.[14]

Only the designated streets in the townships of Lemont, Palos, Orland, Bremen, Lyons (south of the rivers) and Wheeling have the blue pentagon signs that are used to demarcate county roads.

• 
  Interstates in Chicago
• 
  The Eisenhower Expressway at the Ashland Avenue Overpass looking east towards downtown. The 'Ike' as it is known locally, runs parallel to the CTA's Blue Line. Both connect the city to the western suburbs.
• 
  South Lake Shore Drive, looking north towards downtown.
• 
  Traffic going southbound on US-41 on a foggy day.
• 
  The intersection of Madison St and State St is regarded as the "zero-zero point" of Chicago.

• Chicago Department of Transportation
• Chicago Pedway
• Chicago Tunnel Company
• Cycling in Chicago
• Horatio G. Loomis
• LaSalle Street Tunnel
• Matthew Laflin
• Philip Maxwell
• Philo Carpenter
• Van Buren Street Tunnel
• Washington Street Tunnel (Chicago)

• Architecture and Building History resources, Chicago History Museum