SBI Route 81 was Lynn Center to Kewaunee. IL-81 is still the same.
SBI Route 82 was the current IL-82 from Nekoma to IL-92, IL-92 east to IL-172, and IL-172 north and east to IL-40. In the 1930's IL-82 was shortened to its current limits of Nekoma to IL-92. The portion thru Tampico became part of IL-226, and later IL-172.
SBI Route 83 was Galva to New Boston on what is now IL-17. There was a ferry crossing to IA at the west end at New Boston. This route was changed to IL-17 in 1940. In 1941 IL-83 was used on roads that had been IL-52 and IL-54 from the IN line at Lansing to the WI line at Antioch. In 1998 there was a slight reroute near Alsip, when IL-83 was routed east on 127th Street then south onto IL-50, extending a multiplex with IL-50.
IL-83A was used on a spur south of what was then IL-83 (Now IL-17) from Keithsburg to near New Boston. IL-83A was pulled in 1940, and the spur has been unnumbered since.

SBI Route 84 was from the Mississippi River across from Muscatine IA to the current junction of IL-192 & US-67.

  • This route is now IL-92 from the river to IL-192, IL-192 from IL-92 to US-67.
  • During 1938 only this route had been part of IL-2.
  • In 1939 it was changed to IL-92.
  • In 1955 IL-92 was rerouted from Rock Island to near Illinois City, and IL-192 was used on the old route.
  • Also in 1955, IL-84 was placed on a former alignment of US-6 near Green Rock and Colona.
  • In 1964 IL-84 replaced IL-80 to the WI line north of Galena due to the construction of I-80. 

IL-84 currently runs from Colona to the WI line thru Henry, Whiteside, Rock Island, Carroll and Jo Daviess Counties.

SBI Route 85 was Rock Island to Alexis. It is now part of US-67.

SBI Route 86 was Silvis to Sterling on several current routes:

  • IL-5, Silvis to Jct. I-80,
  • I-88/IL-92, Jct. I-80/IL-92/IL-5 to Exit 2,
  • Unnumbered ("Former IL-2") to Sterling.

In 1937 IL-86 was changed to IL-2. Over the years IL-2 was changed several times on this route.

SBI Route 87 was supposed to be a spur from Dixon, but was never built. In 1941 it was used on a new road from Peoria to Lacon. In 1956 IL-87 was extended to Hennepin. In 1969 IL-87 was changed to IL-26.
SBI Route 88 was Peoria to Sterling. In 1938 IL-88 was extended north to Mt. Carroll, replacing IL-40 which had been on this route. In 1995 IL-88 was changed to IL-40 for its entire route, and IL-40 was extended across the Illinois River to East Peoria. This was changed to eliminate a conflict with I-88 which had changed in 1987 from IL-5.
IL-88A was from near Camp Grove to Wyoming which was replaced by IL-17 in 1938.

I-88 is the Ronald Reagen Memorial Tollway from Sterling east to Elmhurst, (Ending at I-294, the Tri-State Tollway) and is a freeway from the Quads at I-80 to Sterling. Total mileage is about 143, 37 free, and 106 toll.

This road was built from Elmhurst to Sugar Grove (Aurora) in 1958 as Toll-US-30, then renumbered to IL-190, then IL-5. It was then extended to the Quad Cities in 1974, and was changed to I-88 in 1987 to allow 65 MPH speed limits when 65 was limited to Interstate posted roads only. It was renamed as the Reagen in 2006.

There is also another I-88 in New York State, but they are not connected.

SBI Route 89 was Dixon to Metamora. The original route was via the current IL-26, Dixon to Hennepin, IL-71 Hennepin to Mark, and IL-89, Mark to Metamora. In 1938 Dixon to Hennepin was changed to IL-26, and Hennepin to Granville was changed to IL-71. IL-89 was extended north to LaMoille, replacing IL-162 on part of this route.
IL-89A was what is now IL-71 from Standard to IL-251 (US-51 at the time). It was changed to IL-71 in 1938.
IL-89B was Lostant to Streator. It was changed to IL-18 in 1939.

IL-89C was Magnolia to Henry. It was changed to IL-18 in 1939.

SBI Route 90 was Laura to Sparland over: IL-90, Laura to Edelstein, IL-40, Edelstein to Jct. IL-17/IL-40, IL-17, Jct. IL-40 to Sparland. In 1938 it was removed from Sparland to IL-40 (Then IL-88) in favor of IL-17.

I-90 runs from Boston to Seattle, and in IL from the IN line on the Chicago Skyway thru Chicago on the Dan Ryan and Kennedy Expressways, and to Rockford and the WI line on the Jane Adams MemorialTollway. The Chicago Skyway however, as of August 1999, is no longer designated as I-90, rather "TO I-90"

It was originally on the Eisenhower. the Dan Ryan, Calumet (Now Bishop Ford) and Kingery Expressways, but was switched with I-94 to use the Chicago Skyway from IN to the Dan Ryan, then headed west on the Eisenhower to the Tri-State, and then to the Northwest Tollway. In 1973 it was moved to the current alignment above. The Kennedy/Northwest Tollway combination was IL-194 prior to I-90 being applied.

The Ike was built as I-90 from 1955 to 1960.

The Chicago Skyway was built in 1958 east of State St and completed west of State to the Dan Ryan in 1962.

The Northwest Tollway was opened to traffic in 1958. In 2007 the Northwest Tollway was renamed the Jane Adams Memorial Tollway in honor of the famed social worker, who went to college in Rockford and operated the Hull House in Chicago.

SBI Route 91 was the current US-150 from Knoxville to Peoria. In 1941 IL-30 was changed to IL-91 to reduce conflicts with nearby US-30. IL-91 currently runs Peoria to US-34 near Kewaunee.

SBI Route 92 was Silvis to LaMoille on part of the current IL-92. In 1939 it was extended to near Muscatine IA on what was then IL-2 and US-67. In 1948 it was extended to Mendota as a second number on US-34. This was later withdrawn, about 1980. In 1955 IL-92 was relocated to a new road west of Milan and the old road became IL-192. In 1980 it was relocated within Rock Island to a freeway that had been IL-199 from 1969 to 1980.

State Routes 92 runs from LaMoille IL to Torrington WY thru Iowa and Nebraska. Why this number continues thru these 4 states is unknown. What makes it even more strange is that State Route 92 doesn't go anywhere important, and takes its time getting there...

Bypass-IL-92 was used during the 1940's from East Moline to Moline, on a route shared with then IL-2 and IL-80. No number is on this route now, it is Colona Road, 42nd St., and 23rd Av. in the area.

SBI Route 93 was Bradford to Galva, with a stub to Toulon. In the early 1930's US-34 took over the west end into Galva. In 1936 the remainder west of Elmira was changed to IL-91, along with the stub to Toulon.

SBI Route 94 was Taylor Ridge to LaHarpe and a spur to Alexis.

  • 1937: The spur was changed to IL-135, IL-94 was extended south to Bowen over IL-95 (LaHarpe to near Durham), IL-95A (Dallas City to Carthage) and IL-36 (Carthage to Bowen).
  • In 1955 it was extended south again to Camp Point, in part replacing IL-102, and extended north to US-67 as a second number on IL-192.

The portion of this road from near Bowen to Carthage is slated to become part of the Western IL Corridor, as an extension of I-172/IL-336 out of Quincy.

IL-94A was Monmouth to Gladstone. In 1937 it was changed to IL-164.
IL-94B was the current IL-135 from Little York to IL-164 (Then IL-94A). It was changed to IL-135 in 1937.

I-94 runs from Billings MT to Port Huron MI, and in IL from the Indiana Line near Lansing on the Tri-State Tollway to the Bishop Ford Freeway (ex Calumet Expressway), north to the Dan Ryan, north on the Kennedy to the Edens, north on the Edens to the Tri-State via the Edens Spur, then to WI on the Tri-State Tollway, about 81 miles in IL. This was once switched with I-90 for a portion in Chicago,see I-90 for details.

The Bishop Ford (ex Calumet Expressway) was first opened in 1950 and extended in 1951, 1952 and 1956 on both ends. The last section was opened in 1962 from the Ryan to 97th.

The Kingery section east of the Bishop Ford was opened in 1950.

The Edens Expressway was opened in part in 1951 and connected to the Kennedy in 1958 and 1959. The Kennedy itself was completed in stages between 1958 and 1962 as was the Ryan.

The Tri-State Tollway (and the Spur) was opened in 1958.

SBI Route 95 was Niota (Mississippi River near Fort Madison IA) to Jct. US-24 & IL-78 east of Lewiston over the following route:

  • IL-9, Niota to Bushnell,
  • IL-41, Bushnell to New Philadelphia,
  • IL-95, New Philadelphia to Cuba,
  • IL-97, Cuba to Lewistown,
  • US-24, Lewistown to IL-78.

In 1937 IL-95 was reduced to Cuba to New Philadelphia, and the above routes took the place of IL-95.

IL-95A was Dallas City to Carthage. It was changed to IL-94 in 1937.
SBI Route 96 was Niota to Kinderhook. In 1941 it was extended north to Terre Haute. In 1942 it was extended south to Hamburg on a new road to meet a ferry crossing to Missouri. In 1950 the southern end was relocated to Kampsville, also at a ferry crossing. In the 1960's the Hamburg ferry quit running.

SBI Route 97 was the current IL-116 from Farmington to IL-94. This was changed in 1934.

  • In 1938 IL-97 was applied Springfield to Petersburg.
  • In 1941 it was extended north to Rapatee, replacing IL-95 and IL-168.
  • In 1942 it was extended to Galesburg, the last 15 miles were a second number on IL-8 and US-150.

In 1965 it was pulled back to the current end at Maquon.

IL-97A was a spur off the current IL-116, Media to Raritan. It was dropped in 1937.
SBI Route 98 was the current US-136 from Macomb to Havana. It was dropped from this route in 1937. In 1939 IL-98 was used on the former IL-9 from Pekin to Morton when IL-9 was relocated.
SBI Route 99 was West Point to Tennessee on: No Number, West Point to IL-94 north of Bowen; IL-94, north of Bowen to Bowen; IL-61 Bowen to US-136 east of Tennessee. It was changed to the above by 1935. In 1936 IL-99 replaced IL-104 from Mt. Sterling to Meredosia In 1941 it was extended north to Brooklyn.

SBI Route 100 was Banner to Kampsville along US-24 from Banner to Lewistown and IL-100 from Lewistown to Kampsville.

  • In 1937 it was swapped with US-24 on a portion south of Canton. The southern end at Kampsville was extended to Hardin, replacing IL-38.
  • In 1939 the southern end was again extended to Grafton.
  • In 1941 it was extended still again to Godfrey on a road that had been US-67 when US-67 was relocated to a new road.
  • In 1987 IL-100 was applied to Grafton from Godfrey on the River Road (AKA McAdams Hwy.).

IL-100 currently runs from Dunfermline (south of Canton) to Alton in Fulton, Schuyler, Cass, Morgan, Scott, Pike, Greene, Calhoun, Jersey and Madison counties. (122103)

Route overview and markers

Updated 3-29-2014