The project concerns the modernization works and putting in 2×2 lanes of the RN4 at the level at the junction with RL 621 from El Fahs to Pk 13,7 through the town of Sidi Aouidet. It originates at Pk 13,70 at the intersection with the RL621 and ends at the level of the governorate limit at Pk 28,2.
This study also includes: