The topography of Laos is largely mountainous, with elevations above 500 meters typically characterized by steep terrain, narrow river valleys, and low agricultural potential. This mountainous landscape extends across most of the north of the country, except for the plain of Vientiane and the Plain of Jars in Xiangkhoang Province. The southern "panhandle" of the country contains large level areas in Savannakh้t and Champasak provinces that are well suited for extensive paddy rice cultivation and livestock rising. Much of Khammouan Province and the eastern part of all the southern provinces are mountainous. Together, the alluvial plains and terraces of the Mekong and its tributaries cover only about 20 percent of the land area.