High Quality Content by WIKIPEDIA articles! The Berm of Western Sahara (also known as the Moroccan Wall) is an approximately 2,700 km-long defensive structure, mostly a sand wall (or "berm"), running through Western Sahara and the southeastern portion of Morocco. It acts as a separation barrier between the Moroccan-controlled areas and the Polisario-controlled section of the territory that lies along its eastern and southern border.