U.S. Route 90 in Louisiana

U.S. Highway 90
US 90 highlighted in red
Route information
Maintained by Louisiana DOTD
Length	297.6 mi.[1] (478.9 km)
Existed	1926–present
Major junctions
West end	I-10 / US 90 at Texas state line east of Orange, TX
Major intersections	I-10 / US 171 / I-210 in Lake Charles US 165 in Iowa Future I-49 / US 167 in Lafayette I-310 / LA 3127 in Boutte US 90 Bus. / Future I-49 west of Westwego I-10 / US 90 Bus. / Future I-49 / US 61 in New Orleans I-610 in New Orleans I-510 / LA 47 in New Orleans US 11 in Eastern New Orleans US 190 east of Slidell
East end	US 90 at Mississippi state line west of Pearlington, MS
Location
Country	United States
State	Louisiana
Parishes	Calcasieu, Jefferson Davis, Acadia, Lafayette, St. Martin, Iberia, St. Mary, Assumption, Terrebonne, Lafourche, St. Charles, Jefferson, Orleans, St. Tammany
Highway system
United States Numbered Highway System List Special Divided Louisiana State Highway System Interstate US State Scenic
← LA 89 → LA 91

U.S. Highway 90 (US 90), one of the major east–west U.S. Highways in the Southern United States, runs through southern Louisiana for 297.6 miles (478.9 km), serving Lake Charles, Lafayette, New Iberia, Morgan City, and New Orleans. Much of it west of Lafayette and east of New Orleans has been supplanted by Interstate 10 (I-10) for all but local traffic, but the section between Lafayette and New Orleans runs a good deal south of I-10.

The stretch between Lafayette and New Orleans is planned as a southern extension of I-49 and is signed as "future corridor I-49". This part of the highway is important to the offshore petroleum industry, as it connects the cities of Lafayette and New Orleans to the port cities along the coast. Most of US 90 from New Iberia to New Orleans that has not already been improved to Interstate grade, is mainly an expressway, excepting the towns traversed through, that can be easily upgraded to freeway standards. The freeway east of Morgan City, bypassing Houma to the north, was originally built as Louisiana Highway 3052 (LS 3052); US 90 was shifted to it from its former alignment (now LA 182) once it was completed.

US 90 replaced almost all of the Louisiana section of the San Diego–St. Augustine running Old Spanish Trail. It was also designated Louisiana Highway 2 (LA 2) until the 1955 renumbering. A long section of the old road, from Lafayette to northeast of Raceland, is now LA 182.