<P> The geography of the United States varies across their immense area . Within the continental U.S., eight distinct physiographic divisions exist, though each is composed of several smaller physiographic subdivisions . These major divisions are: </P> <Ul> <Li> Laurentian Upland - part of the Canadian Shield that extends into the northern United States Great Lakes area . </Li> <Li> Atlantic Plain - the coastal regions of the eastern and southern parts includes the continental shelf, the Atlantic Coast and the Gulf Coast . </Li> <Li> Appalachian Highlands - lying on the eastern side of the United States, it includes the Appalachian Mountains, the Watchung Mountains, the Adirondacks and New England province originally containing the Great Eastern Forest, a stretch of mixed temperature and subtropical montane forests, some of which are rainforests . </Li> <Li> Interior Plains - part of the interior continental United States, it includes the Great Plains, as well as a number of highland and mountainous regions, like the Black Hills, dense cave systems, painted hills and badland features . </Li> <Li> Interior Highlands - also part of the interior continental United States, this division includes the Ozark Plateau, the Ouachita Mountains, and other smaller mountain systems . This region is located largely in the warm temperate / subtropical moist and dry forest biomes . </Li> <Li> Rocky Mountain System - one branch of the Cordilleran system lying far inland in the western states . </Li> <Li> Intermontane Plateaus - also divided into the Columbia Plateau, the Colorado Plateau and the Basin and Range Province, it is a system of plateaus, basins, ranges and gorges between the Rocky and Pacific Mountain Systems . It is the setting for the Grand Canyon, the Great Basin and Death Valley . </Li> <Li> Pacific Mountain System - the coastal mountain ranges and features in the west coast of the United States . </Li> </Ul> <Li> Laurentian Upland - part of the Canadian Shield that extends into the northern United States Great Lakes area . </Li> <Li> Atlantic Plain - the coastal regions of the eastern and southern parts includes the continental shelf, the Atlantic Coast and the Gulf Coast . </Li>

Which north american region is located only in the united states