I-12

About I-12

From Baton Rouge, LA (I-10) to Slidell, LA (I-10/I-59)

Interstate 12 is an east-west route entirely within southeastern Louisiana, running about 85 miles from Baton Rouge to Slidell near the Mississippi state line. It functions as a northern bypass of the I-10 corridor, allowing through traffic to skip the longer and more flood-prone route through New Orleans by cutting across the higher ground north of Lake Pontchartrain. Both of its endpoints connect to Interstate 10.

The highway passes through the growing suburban communities north of the lake, including Hammond and the area around Covington and Mandeville. It carries heavy commuter and freight traffic and serves as an important hurricane evacuation route, moving people inland and away from the coast. The terrain is low and flat, typical of the Gulf Coast plain.

State-by-state mileage

State	Miles
Louisiana	85.6
Total	85.6

History

Interstate 12 was designated in 1960 and built to provide a shorter east-west path across southeastern Louisiana that avoids the New Orleans urban area. It connects to I-10 at both ends, forming the top of a triangle with I-10 and I-55 around Lake Pontchartrain.

The route has been widened over the years to handle suburban growth in the parishes north of the lake and its role in regional evacuation planning.

Major cities and places

Did you know

• It serves as a northern bypass of I-10 around the New Orleans area.
• Both ends of the route connect to I-10.
• It is an important hurricane evacuation route for southeastern Louisiana.
• The route lies entirely within Louisiana, north of Lake Pontchartrain.