On the western end of the north coast of Honduras, the outstanding river is the Ulúa, whose basin is formed by the plain of Sula. In the south, the gradually descending steps of the Cordilleras with the open avenues of the Ulúa on the west and her tributaries, the Lindo due south and the Comayagua at the east, bring contact to the wet valley of Sula from the semi-arid interior. Eastward lies the low margin of coast and the lagoons and river systems of the Pijol range. West and southwest is mountain land with an important river valley, the Chamelicon, which merges into the Sula plain. At the north is the open sea, bringing to this region varied influences from many and distant places.