Interstate 55 (I-55) is a major

Interstate Highway The Dwight D. Eisenhower National System of Interstate and Defense Highways, commonly known as the Interstate Highway System, or the Eisenhower Interstate System, is a network of controlled-access highways that forms part of the National Hi ...

in the central United States. As with most primary Interstates that end in a five, it is a major cross-country, north–south route, connecting the

Gulf of Mexico The Gulf of Mexico () is an oceanic basin and a marginal sea of the Atlantic Ocean, mostly surrounded by the North American continent. It is bounded on the northeast, north, and northwest by the Gulf Coast of the United States; on the southw ...

to the

Great Lakes The Great Lakes, also called the Great Lakes of North America, are a series of large interconnected freshwater lakes spanning the Canada–United States border. The five lakes are Lake Superior, Superior, Lake Michigan, Michigan, Lake Huron, H ...

. The highway travels from LaPlace, Louisiana, at I-10 to

Chicago Chicago is the List of municipalities in Illinois, most populous city in the U.S. state of Illinois and in the Midwestern United States. With a population of 2,746,388, as of the 2020 United States census, 2020 census, it is the List of Unite ...

, Illinois, at Lake Shore Drive ( US 41), near McCormick Place. The major cities that I-55 connects to are (from south to north)

New Orleans New Orleans (commonly known as NOLA or The Big Easy among other nicknames) is a Consolidated city-county, consolidated city-parish located along the Mississippi River in the U.S. state of Louisiana. With a population of 383,997 at the 2020 ...

, Louisiana; Jackson, Mississippi; Memphis, Tennessee; St. Louis, Missouri; and Chicago, Illinois. The section of I-55 between Chicago and St. Louis was built as an alternate route for U.S. Route 66 (US 66). The Interstate crosses the

Mississippi River The Mississippi River is the main stem, primary river of the largest drainage basin in the United States. It is the second-longest river in the United States, behind only the Missouri River, Missouri. From its traditional source of Lake Ita ...

twice: once at Memphis and again at St. Louis.

History

When it was realized that a national highway system was needed, the Federal Aid Highway Act of 1956 provided for a highway replacing the old US 66 which I-55 filled. I-55 was originally constructed in the 1960s, to extend a section of US 66 between I-294 and Gardner which had been converted into a freeway and had Interstate signage installed in 1960. During the rest of the 1960s, I-55 was built in portions throughout Illinois, eventually connecting St. Louis to

, where it became the fourth direct route between them. As it goes southward, most of the Interstate was purpose-built during the 1960s and 1970s. The entire length was completed in 1979.

Route description

, - , LA , 65.81 , 105.91 , - , MS , 290.41 , 467.37 , - , TN , 12.28 , 19.76 , - , AR , 72.22 , 116.22 , - , MO , 210.45 , 338.69 , - , IL , 293.80 , 472.72 , - , Total , 964.25 , 1,551.81

Louisiana

Louisiana Louisiana ( ; ; ) is a state in the Deep South and South Central regions of the United States. It borders Texas to the west, Arkansas to the north, and Mississippi to the east. Of the 50 U.S. states, it ranks 31st in area and 25 ...

, I-55 runs nearly from south to north, from I-10 near Laplace ( west of

) to the

Mississippi Mississippi ( ) is a U.S. state, state in the Southeastern United States, Southeastern and Deep South regions of the United States. It borders Tennessee to the north, Alabama to the east, the Gulf of Mexico to the south, Louisiana to the s ...

state line near Kentwood. Approximately a third of the distance consists of the Manchac Swamp Bridge, a nearly causeway, often cited as the third-longest viaduct in the world.

Mississippi

, I-55 runs from the

border near Osyka to Southaven on the

Tennessee Tennessee (, ), officially the State of Tennessee, is a landlocked U.S. state, state in the Southeastern United States, Southeastern region of the United States. It borders Kentucky to the north, Virginia to the northeast, North Carolina t ...

border, just south of

Memphis, Tennessee Memphis is a city in Shelby County, Tennessee, United States, and its county seat. Situated along the Mississippi River, it had a population of 633,104 at the 2020 United States census, 2020 census, making it the List of municipalities in Tenne ...

. Noteworthy cities and towns that I-55 passes through or close by to are Brookhaven, McComb, Jackson, and

Grenada Grenada is an island country of the West Indies in the eastern Caribbean Sea. The southernmost of the Windward Islands, Grenada is directly south of Saint Vincent and the Grenadines and about north of Trinidad and Tobago, Trinidad and the So ...

. This highway parallels US 51 in its path roughly through the center of Mississippi. The from Hernando to the Tennessee state line coincide with the newer

I-69 Interstate 69 (I-69) is an Interstate Highway in the United States currently consisting of eight unconnected segments. The longest segment runs from Evansville, Indiana, northeast to the Canada–United States border, Canadian border in Po ...

. The Mississippi section of I-55 is defined in the Mississippi Code § 65-3-3.

Tennessee

I-55 in Tennessee lies entirely within the city of Memphis, passing through the southern and western parts of the city and providing a bypass of downtown for motorists who do not want to take I-240 and I-40 through downtown to cross the Mississippi River. The western portion of this highway, which passes through an industrialized section of the city, contains numerous low-clearance bridges and also a very tight 270-degree cloverleaf turn northbound at Crump Boulevard. The

Tennessee Department of Transportation The Tennessee Department of Transportation (TDOT) is the department of transportation for the State of Tennessee, with multimodal responsibilities in roadways, aviation, public transit, waterways, and railroads. It was established in 1915 as the ...

(TDOT) currently has an interchange improvement project for this portion. Heavy truck traffic heading to and from Arkansas in this area is hence directed to detour via I-240 and I-40. For the Tennessee stretch of the Interstate, the usual national freeway

speed limit Speed limits on road traffic, as used in most countries, set the legal maximum speed at which vehicles may travel on a given stretch of road. Speed limits are generally indicated on a traffic sign reflecting the maximum permitted speed, express ...

of is reduced to .

Arkansas

I-55 enters Arkansas from Tennessee as it crosses the Mississippi River on the Memphis & Arkansas Bridge. It overlaps I-40 for approximately in West Memphis. After separating from I-40, I-55 turns northward and runs with US 61, US 63, and US 64 until US 64 exits in through Marion. I-55/US 61/US 63 continues north through Crittenden County through rural farms of the Arkansas delta, including an interchange with I-555/US 63 in Turrell. I-55 passes through Blytheville, where it has a junction with Highway 18 (AR 18) before entering Missouri. I-55 parallels US 61 in its path through Arkansas, which it continues to do after crossing into Missouri.

Missouri

In Missouri, I-55 runs from the southeastern part of the state, at the Arkansas border, to St. Louis. In the southern part of the state, I-55 meets I-57 in Sikeston. Then I-55 goes north to St. Louis, where I-44 merges in with I-55, and then I-64 (on the Poplar Street Bridge), when crossing the Mississippi River into Illinois. Among the cities and towns served by I-55 in Missouri are Sikeston, Cape Girardeau, and St. Louis. As noted above, I-55 parallels US 61 for most of its course through Missouri, from the Arkansas border to the southern portion of St. Louis County.

Illinois

Through Illinois, I-55 largely follows the 1940 alignment of the former US 66, now Historic US 66 (Illinois Route 66 Scenic Byway). It runs from the Poplar Street Bridge in East St. Louis to US 41 in Chicago, passing around the state capital of Springfield and the metro area of Bloomington– Normal. Within Illinois, I-55 goes by several names. Near the I-270/ I-70 split, it is referred to as the Paul Simon Freeway after former US Senator Paul Simon, who began his political career in this region. Further north, between the St. Louis area and Springfield, I-55 is named the Vince Demuzio Expressway for former Illinois State Senator Vince Demuzio. Finally, in the Chicago area between the I-80 interchange near Joliet and I-55's eastern terminus at US 41 ( Lake Shore Drive) in

, the expressway is referred to as the Adlai E. Stevenson Expressway (previously called the Southwest Expressway) in honor of former Illinois governor Adlai E. Stevenson II, who was a two-time Democratic nominee for President of the United States and also the US Ambassador to the

United Nations The United Nations (UN) is the Earth, global intergovernmental organization established by the signing of the Charter of the United Nations, UN Charter on 26 June 1945 with the stated purpose of maintaining international peace and internationa ...

under Presidents John F. Kennedy and Lyndon B. Johnson. In July 2018, the stretch of I-55 from I-294 to milemarker 202 near Pontiac was renamed as Barack Obama Presidential Expressway, after former President

Barack Obama Barack Hussein Obama II (born August 4, 1961) is an American politician who was the 44th president of the United States from 2009 to 2017. A member of the Democratic Party, he was the first African American president in American history. O ...

. When the stretch of I-55 through Illinois was being planned during the 1960s, the state's governor, Otto Kerner Jr., made an effort to have it routed close to the larger city of Peoria instead of the straighter route through the Bloomington–Normal area. This ultimately failed plan was ridiculed in the press as the so-called "Kerner Curve". The need for a freeway connection between Springfield and Peoria was later filled by the spur route I-155. This also connects with nearby Lincoln and Morton and forms a triangle between the three population centers in Central Illinois.

Junction list

;Louisiana : in LaPlace : northeast of LaPlace. The highways travel concurrently to Hammond. : in Hammond : in Hammond ;Mississippi : in McComb. The highways travel concurrently to

Summit A summit is a point on a surface that is higher in elevation than all points immediately adjacent to it. The topographic terms acme, apex, peak (mountain peak), and zenith are synonymous. The term (mountain top) is generally used only for ...

. : south-southwest of Brookhaven : in Crystal Springs. The highways travel concurrently to Jackson. : in Jackson. I-20/I-55/US 49 travel concurrently to Richland. : in Ridgeland : in Winona : in Batesville : in Hernando. The highways travel concurrently to

. ;Tennessee : in Memphis : in Memphis : in Memphis : in Memphis. I-55/US 61 travels concurrently to Turrell, Arkansas. I-55/US 64 travels concurrently to Marion, Arkansas. I-55/US 70/US 79 travels concurrently to West Memphis, Arkansas. ;Arkansas : in West Memphis. The highways travel concurrently through West Memphis. : in West Memphis. I-55/US 63 travels concurrently to Turrell. : in Turrell, Arkansas. : in Blytheville ;Missouri : east of Steele. The highways travel concurrently to Portageville. : in Hayti : in New Madrid : north of New Madrid : on the Sikeston–

Miner A miner is a person who extracts ore, coal, chalk, clay, or other minerals from the earth through mining. There are two senses in which the term is used. In its narrowest sense, a miner is someone who works at the rock face (mining), face; cutt ...

city line : in Miner : in Scott City. The highways travel concurrently to Cape Cirardeau. : in Cape Girardeau : north-northeast of Jackson : south-southeast of Festus : in Festus : on the Concord– Mehlville CDP line : on the Concord– Green Park–Mehlville line : on the McKinley Heights– Soulard, St. Louis neighborhood line. The highways travel concurrently to Downtown St. Louis. : in Downtown, St. Louis. I-55/I-64 travels concurrently to East St. Louis, Illinois. I-55/US 40 travels concurrently to Troy, Illinois. ;Illinois : in East St. Louis. I-55/I-70 travels concurrently to northwest of Troy. : in Collinsville : northwest of Troy : in Springfield. The highways travel concurrently through Springfield. : northwest of Lincoln : southeast of McLean : in Bloomington. I-55/I-74 travels concurrently to northwest of Normal. I-55/US 51 travels concurrently to Normal. : in Bloomington : in Normal : in Chenoa : in Channahon : in Channahon : in Shorewood : in Joliet : on the Bolingbrook– Woodridge village line : on the Burr Ridge– Indian Head Park– Countryside village line : on the Countryside– Hodgkins village line : in Armour Square,

: in Near South Side, Chicago

Auxiliary routes

*Spur to

Jonesboro, Arkansas Jonesboro () is a city located on Crowley's Ridge in the northeastern corner of the U.S. State of Arkansas. Jonesboro is one of two county seats of Craighead County, Arkansas, Craighead County. In 2023, the city had an estimated population of ...

: I-555 * Caruthersville, Missouri to Dyersburg, Tennessee: I-155 * St. Louis, Missouri, area: I-255 *Spur to

Peoria, Illinois Peoria ( ) is a city in Peoria County, Illinois, United States, and its county seat. Located on the Illinois River, the city had a population of 113,150 as of the 2020 United States census, 2020 census, making it the List of municipalities in Ill ...

: I-155 *In the western suburbs of

Chicago, Illinois Chicago is the List of municipalities in Illinois, most populous city in the U.S. state of Illinois and in the Midwestern United States. With a population of 2,746,388, as of the 2020 United States census, 2020 census, it is the List of Unite ...

: I-355

References

External links

*
Illinois Highway Ends: Interstate 55
{{Authority control 55