List of numbered highways in Louisiana

Interstate 10, south Louisiana's east-west artery, includes cities of New Orleans, Baton Rouge, Lafayette
Lafayette, Louisiana
Lafayette is a city in and the parish seat of Lafayette Parish, Louisiana, United States, on the Vermilion River. The population was 120,623 at the 2010 census...

and Lake Charles
Lake Charles, Louisiana
Lake Charles is the fifth-largest incorporated city in the U.S. state of Louisiana, located on Lake Charles, Prien Lake, and the Calcasieu River. Located in Calcasieu Parish, a major cultural, industrial, and educational center in the southwest region of the state, and one of the most important in...

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Interstate 12, Baton Rouge to Slidell, New Orleans bypass
Interstate 20, north Louisiana's east-west artery, includes cities of Shreveport and Monroe, Louisiana
Monroe, Louisiana
Monroe is a city in and the parish seat of Ouachita Parish, Louisiana, United States. As of the 2000 census, the city had a total population of 53,107, making it the eighth largest city in Louisiana. A July 1, 2007, United States Census Bureau estimate placed the population at 51,208, but 51,636...

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Interstate 49, Lafayette to Shreveport, expansion of 49 south to New Orleans, replacing part of U.S.