Interstate 12 (I-12) is an

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

located entirely within the

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its sove ...

Louisiana Louisiana , group=pronunciation (French: ''La Louisiane'') is a U.S. state, state in the Deep South and South Central United States, South Central regions of the United States. It is the List of U.S. states and territories by area, 20th-smal ...

. It spans a total of in an east–west direction from

I-10 Interstate 10 (I-10) is the southernmost cross-country highway in the American Interstate Highway System. I-10 is the fourth-longest Interstate in the United States at , following I-90, I-80, and I-40. This freeway is part of the originally p ...

Baton Rouge Baton Rouge ( ; ) is a city in and the capital of the U.S. state of Louisiana. Located the eastern bank of the Mississippi River, it is the parish seat of East Baton Rouge Parish, Louisiana's most populous parish—the equivalent of countie ...

to an interchange with both I-10 and I-59 in Slidell. Along the way, it passes through the city of

Hammond Hammond may refer to: People * Hammond Innes (1913–1998), English novelist * Hammond (surname) * Justice Hammond (disambiguation) Places Antarctica * Hammond Glacier, Antarctica Australia *Hammond, South Australia, a small settlement in South ...

, where it intersects

I-55 Interstate 55 (I-55) is a major Interstate Highway 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 to the Great Lakes. The h ...

and US Route 51 (US 51). It also serves the cities of Ponchatoula and Denham Springs, as well as the St. Tammany Parish cities of

Covington Covington may refer to: People * Covington (surname) Places United Kingdom * Covington, Cambridgeshire * Covington, South Lanarkshire United States * Covington, Georgia * Covington, Indiana * Covington, Kentucky, the largest American cit ...

and Mandeville. Skirting the northern shore of

Lake Pontchartrain Lake Pontchartrain ( ) is an estuary located in southeastern Louisiana in the United States. It covers an area of with an average depth of . Some shipping channels are kept deeper through dredging. It is roughly oval in shape, about from wes ...

, I-12 serves as both a northern bypass of the

New Orleans metropolitan area The New Orleans metropolitan area, designated the New Orleans–Metairie metropolitan statistical area by the U.S. Office of Management and Budget, or simply Greater New Orleans (french: Grande Nouvelle-Orléans, es, Gran Nueva Orleans), is a m ...

and an alternate route for I-10, which serves the city of

New Orleans New Orleans ( , ,New Orleans

US 190 corridor and traverses the North Shore of Lake Pontchartrain in the southeastern portion of the state. The interstate's length is short for a mainline interstate and is comparable with the country's longest auxiliary interstates. It is one of the shortest mainline interstates to terminate at the same route (I-10) at either end. Apart from serving the various communities of the North Shore, I-12 acts as a long

bypass Bypass may refer to: * Bypass (road), a road that avoids a built-up area (not to be confused with passing lane) * Flood bypass of a river Science and technology Medicine * Bypass surgery, a class of surgeries including for example: ** Heart bypas ...

of New Orleans and is heavily used as a shortcut for through traffic on I-10. While I-10 curves to the south to pass through the city limits, I-12 takes a more direct alignment, reducing the distance between Baton Rouge and Slidell by about . In 1993, the

Louisiana State Legislature The Louisiana State Legislature (french: Législature d'État de Louisiane) is the state legislature of the U.S. state of Louisiana. It is a bicameral body, comprising the lower house, the Louisiana House of Representatives with 105 represen ...

designated I-12 as the Republic of West Florida Parkway. In 2003, signs identifying the highway's official name and bearing the flag of the

Republic of West Florida The Republic of West Florida ( es, República de Florida Occidental, french: République de Floride occidentale), officially the State of Florida, was a short-lived republic in the western region of Spanish West Florida for just over months ...

were erected by the

Louisiana Department of Transportation and Development The Louisiana Department of Transportation and Development (DOTD) is a state government organization in the United States, in charge of maintaining public transportation, roadways, bridges, canals, select levees, floodplain management, port facili ...

(LADOTD) in order to highlight the unique history of Louisiana's

Florida Parishes The Florida Parishes ( es, Parroquias de Florida, french: Paroisses de Floride), on the east side of the Mississippi River—an area also known as the Northshore or Northlake region—are eight parishes in the southeastern portion of the U.S. sta ...

. Louisiana is in the process of widening I-12 to three lanes in each direction in locations such as Covington and Mandeville where the interstate is still two lanes in each direction.

Route description

I-12 West End - Exit 1A - I-10 East (42134288362)

Baton Rouge to Hammond

From the west, I-12 begins east of downtown

in East Baton Rouge Parish at an interchange with

known as the I-10/I-12 split. While I-10 heads to the southeast toward the

, I-12 proceeds eastward toward the North Shore of

. Before leaving Baton Rouge, I-12 intersects some of its major arteries, including Louisiana Highway 3064 (LA 3064, Essen Lane) and LA 73 (

Jefferson Highway The Jefferson Highway was an automobile highway stretching through the central United States from New Orleans, Louisiana, to Winnipeg, Manitoba, Canada. The Jefferson Highway was replaced with the new numbered US Highway system in the late 1920s. ...

) via LA 1068 (Drusilla Lane). It then passes through a cloverleaf interchange with US 61 (

Airline Highway Airline Highway is a divided highway in the U.S. state of Louisiana, built in stages between 1925 and 1953 to bypass the older Jefferson Highway. It runs , carrying U.S. Highway 61 from New Orleans northwest to Baton Rouge and U.S. Highway ...

). These three exits serve several of the area's key medical and shopping centers, such as the Our Lady of the Lake Regional Medical Center and Cortana Mall. The final exit in Baton Rouge is an interchange with LA 3245 (O'Neal Lane), which serves the Ochsner Medical Center and eastern suburbs. later, I-12 reaches the

Amite River The Amite River (french: Rivière Amite) is a tributary of Lake Maurepas in Mississippi and Louisiana in the United States. It is about long. It starts as two forks in southwestern Mississippi and flows south through Louisiana, passing Greater ...

, where it enters Livingston Parish and the city of Denham Springs. I-12 skirts the southern edge of town, providing interchanges with LA 3002 (South Range Avenue) and LA 1026 (Juban Road). East of Denham springs, I-12 skirts the southern edge of Livingston Parish's only other city,

Walker Walker or The Walker may refer to: People *Walker (given name) *Walker (surname) *Walker (Brazilian footballer) (born 1982), Brazilian footballer Places In the United States *Walker, Arizona, in Yavapai County *Walker, Mono County, California * ...

. The interstate's sole exit in Walker is exit 15, an interchange with LA 447. Past Walker are smaller communities in the eastern half of the parish. Exits include: LA 63 serving Livingston (exit 22), LA 441 serving Holden (exit 29), and LA 43 serving Albany and Springfield (exit 32). Shortly after crossing the Natalbany River into

Tangipahoa Parish Tangipahoa Parish (; French: ''Paroisse de Tangipahoa'') is a parish located in the southeast corner of the U.S. state of Louisiana. As of the 2010 census, the population was 121,097. The parish seat is Amite City, while the largest city is ...

, I-12 intersects LA 1249, which leads to the communities of

Baptist Baptists form a major branch of Protestantism distinguished by baptizing professing Christianity, Christian believers only (believer's baptism), and doing so by complete Immersion baptism, immersion. Baptist churches also generally subscribe ...

and Pumpkin Center. later, I-12 enters into a cloverleaf interchange with

at the southeast corner of

, the largest city in Tangipahoa Parish. I-55 heads toward

Jackson, Mississippi Jackson, officially the City of Jackson, is the Capital city, capital of and the List of municipalities in Mississippi, most populous city in the U.S. state of Mississippi. The city is also one of two county seats of Hinds County, Mississippi, ...

on the north and

New Orleans New Orleans ( , ,New Orleans

US 51 crosses I-12, but the two roads do not intersect. There is instead an interchange with US 51 Business, which serves downtown Hammond, as well as the city of Ponchatoula to the south.

Hammond to Slidell

East of Hammond are two rural exits in southeastern Tangipahoa Parish: LA 3158 (Airport Road) to the

Hammond Northshore Regional Airport Hammond Northshore Regional Airport is a city-owned, public-use, joint civil-military, general aviation airport located three nautical miles (6 km) northeast of the central business district of Hammond, a city in Tangipahoa Parish, Louis ...

, and LA 445 to

Robert The name Robert is an ancient Germanic given name, from Proto-Germanic "fame" and "bright" (''Hrōþiberhtaz''). Compare Old Dutch ''Robrecht'' and Old High German ''Hrodebert'' (a compound of '' Hruod'' ( non, Hróðr) "fame, glory, h ...

. Just after crossing into St. Tammany Parish, I-12 curves to the southeast and begins to parallel the North Shore of Lake Pontchartrain. An interchange with LA 1077 serves the town of Madisonville to the south. The following exit, an interchange with LA 21, also connects to Madisonville as well as the parish seat of

to the north. Immediately before crossing the Tchefuncte River, an exit to Pinnacle Parkway and East Brewster Road serves the growing shopping area east of LA 21. east of the bridge, I-12 passes through an interchange with US 190 between Covington and Mandeville. This section of US 190 serves as St. Tammany's busiest north–south thoroughfare, connecting Covington and surrounding points with the

Lake Pontchartrain Causeway The Lake Pontchartrain Causeway (french: Chaussée du lac Pontchartrain), also known simply as The Causeway, is a fixed link composed of two parallel bridges crossing Lake Pontchartrain in southeastern Louisiana, United States. The longer of the ...

, a -long bridge leading to New Orleans. Further exits in St. Tammany Parish west of Slidell include LA 59 to Mandeville and Abita Springs, LA 1088 to LA 36, and LA 434 to

Lacombe Lacombe may refer to: Places * Lacombe, Alberta, Canada * Lacombe County, Alberta, Canada * Lacombe, Louisiana, United States * Lacombe, Aude, France People * Albert Lacombe (1827–1916), oblate missionary to the Cree and Blackfoot * Bernar ...

. east of the Lacombe exit, I-12 passes through an interchange with Airport Drive, which connects to Slidell Airport due north. At this exit, I-12 enters the northern edge of Slidell. An interchange with US 11 connects to the downtown area. Less than later, I-12 reaches its eastern terminus at a major interchange with I-10 and I-59 at the northeast corner of town. From this interchange, I-10 heads southwest toward New Orleans and east toward

Bay St. Louis, Mississippi Bay St. Louis is a city in and the county seat of Hancock County, Mississippi, in the United States. Located on the Gulf Coast on the west side of the Bay of St. Louis, it is part of the Gulfport–Biloxi Metropolitan Statistical Area. As of ...

while I-59 heads north toward

Hattiesburg, Mississippi Hattiesburg is a city in the U.S. state of Mississippi, located primarily in Forrest County (where it is the county seat and largest city) and extending west into Lamar County. The city population was 45,989 at the 2010 census, with the populat ...

History

I-12 was added to the highway system on October 17, 1957, with I-12 running from I-10 in Baton Rouge to I-59 north of Slidell. By the mid-1960s, the routes had been realigned to their current configuration, with I-12 and I-59 both ending at I-10 near Slidell. The route was opened to traffic in several sections between January 1967 and June 1976. With major damage to the

I-10 Twin Span Bridge The I-10 Twin Span Bridge, a nearly causeway officially known as the Frank Davis "Naturally N'Awlins" Memorial Bridge, consists of two parallel trestle bridges. These parallel bridges cross the eastern end of Lake Pontchartrain in southern Lo ...

across

from Hurricane Katrina, I-12 was temporarily ''functioning'' as I-10 between Baton Rouge and Slidell. On October 14, 2005, the eastbound span of I-10 over Lake Pontchartrain reopened to two-way traffic. The westbound span of I-10 reopened on January 6, 2006, with speed, weight and size restrictions, relieving I-12 of much of the congestion that was clogging it from the

to the junction with I-10 and I-59. LA DOTD widened the interstate to three lanes in each direction from O'neal Lane (exit 7) to Juban Road (exit 12) in 2012, later extending to exit 15 (Walker South Road/LA 447) in 2013 and west of Satsuma (exit 19) in 2015. In St. Tammany Parish, near Slidell, a third lane was added from the

/I-12/ I-59 split to just west of US 11 in 2012 and to Airport Drive/Northshore Boulevard (exit 80) in 2016. The I-10/I-12/I-59 split, notorious for rough pavement, was repaved in 2015.

Exit list

Notes

References

External links

La DOTD State, District, and Parish Maps
{{DEFAULTSORT:I012 12 12 Transportation in East Baton Rouge Parish, Louisiana Transportation in Livingston Parish, Louisiana Transportation in St. Tammany Parish, Louisiana Transportation in Tangipahoa Parish, Louisiana