The Sudanian Savanna is a broad belt of tropical savanna that runs east and west across the African continent, from the Atlantic Ocean in the west to the Ethiopian Highlands in the east. The Sahel, a belt of drier grasslands and acacia savannas, lies to the north, between the Sudanian Savanna and the Sahara Desert. To the south the forest-savanna mosaic is a transition zone between the Sudanian Savanna and the Guinean moist forests and Congolian forests that lie nearer the equator.