The sea dike running southwards from Ba Lat estuary (the Red River) through Ha Lan estuary (the Co River), and Lach Giang estuary (the Ninh Co River) ends at Day estuary (the Day River), marking the far end of the fertile coastal land of Nam Dinh province. The small, high and winding dike flows like a wave and offers those who travel on it a great site for the eyes.