During this time, the highway briefly passes through a corner of Beauregard Parish before crossing back into Calcasieu Parish. Shortly afterward, LA 12 passes the DeQuincy Industrial Airpark, simultaneously entering the small city of DeQuincy. It then curves slightly more to the northeast and away from the railroad line. After passing the local middle and high schools, the route curves due east into town on West 4th Street. LA 12 intersects LA 389 (Cole Street) at the latter's southern terminus then makes a jog across the railroad tracks onto East 4th Street, entering the city's historic district. Signs direct visitors to the DeQuincy Railroad Museum, located one block to the north at the convergence of two branches of the KCS Railway. Shortly after a second grade crossing, LA 12 intersects LA 27, which heads northward along Page Street toward DeRidder. Widening to accommodate a center turning lane, the two highways run east concurrently for two blocks until LA 27 turns south onto South Grand Avenue, heading toward Sulphur.