Somalia has the longest national coastline (3025 km) in Africa with an estimated shelf area (depth 0–200 m) of 32 500 km2. The country is divided into the northern coastal plain of Guban, which has a semi-arid terrain; the northern highlands with rugged mountain ranges containing the country’s highest peak (2407 m); and the Ogaden region which descends to the south from the highlands and which consists of shallow plateau valleys, wadis, and broken mountains. The latter region continues to the Mudug plain in central Somalia.