Interstate 12
Interstate 12 (I-12) is an Interstate Highway located entirely within the U.S. state of Louisiana. It spans a total of in an east–west direction from I-10 in Baton Rouge to an interchange with both I-10 and I-59 in Slidell. Along the way, it passes through the city of Hammond, where it intersects I-55 and US 51. It also serves the smaller cities of Denham Springs and Ponchatoula, as well as the St. Tammany Parish cities of Covington and Mandeville. Skirting the northern shore of Lake Pontchartrain, I-12 serves as a northern bypass of the New Orleans metropolitan area and as an alternate route for I-10, which serves the city of New Orleans itself.

I-12 parallels the older 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 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 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 were erected by the Louisiana Department of Transportation and Development (LADOTD) in order to highlight the unique history of Louisiana's Florida Parishes.

Louisiana is in the process of widening I-12 to three lanes in locations where the interstate is still two lanes in each direction.
Q94247
Interstate Highway
Concept
Q35657
U.S. state
Concept
Q1588
Louisiana
LOC
Q2398679
I-10
LOC
Q28218
Baton Rouge
LOC
Q94378
I-59
LOC
Q988156
Slidell
LOC
Q1014071
Hammond
LOC
Q2399190
I-55
LOC
Q22084873
US 51
LOC
Q2777726
Denham Springs
LOC
Q682639
Ponchatoula
LOC
Q506921
St. Tammany Parish
LOC
Q1014171
Covington
LOC
Q2507175
Mandeville
LOC
Q1331750
Lake Pontchartrain
LOC
Q7010868
New Orleans metropolitan area
LOC
Q4816910
US 190
LOC
Q1828268
short for a mainline interstate
UNK
Q1894739
auxiliary interstates
LOC
Q1779930
bypass
Concept
Q34404
New Orleans
LOC
Q6689290
Louisiana State Legislature
LOC
Q13258120
Republic of West Florida
LOC
Q2400783
Louisiana Department of Transportation and Development
LOC
Q1245253
Florida Parishes
LOC
Q93395
Interstate 12
LOC
1993-01-01T00:00:00Z^^http://www.w3.org/2001/XMLSchema#dateTime
1993
DATE
2003-01-01T00:00:00Z^^http://www.w3.org/2001/XMLSchema#dateTime
2003
DATE
+12^^http://www.w3.org/2001/XMLSchema#decimal
12
NUMBER
-12^^http://www.w3.org/2001/XMLSchema#decimal
-12
NUMBER
-10^^http://www.w3.org/2001/XMLSchema#decimal
-10
NUMBER
-10^^http://www.w3.org/2001/XMLSchema#decimal
-10
NUMBER
-59^^http://www.w3.org/2001/XMLSchema#decimal
-59
NUMBER
-55^^http://www.w3.org/2001/XMLSchema#decimal
-55
NUMBER
+51^^http://www.w3.org/2001/XMLSchema#decimal
51
NUMBER
-12^^http://www.w3.org/2001/XMLSchema#decimal
-12
NUMBER
-10^^http://www.w3.org/2001/XMLSchema#decimal
-10
NUMBER
-12^^http://www.w3.org/2001/XMLSchema#decimal
-12
NUMBER
+190^^http://www.w3.org/2001/XMLSchema#decimal
190
NUMBER
-10^^http://www.w3.org/2001/XMLSchema#decimal
-10
NUMBER
-12^^http://www.w3.org/2001/XMLSchema#decimal
-12
NUMBER
-10^^http://www.w3.org/2001/XMLSchema#decimal
-10
NUMBER
-10^^http://www.w3.org/2001/XMLSchema#decimal
-10
NUMBER
-12^^http://www.w3.org/2001/XMLSchema#decimal
-12
NUMBER
-12^^http://www.w3.org/2001/XMLSchema#decimal
-12
NUMBER
-12^^http://www.w3.org/2001/XMLSchema#decimal
-12
NUMBER
highway system
terminus location
terminus
terminus location
located in the administrative territorial entity
owned by