RiversColumbia River: Headwaters are in Canada (BC), then flows through Washington and then along the border between Oregon and Washington and finally into the Pacific Ocean.
MountainsOuachita Mountains: situated across the border between Oklahoma and Arkansas. The Eastern edge is at about Little Rock, Arkansas.
Site and SituationThe situation of the USA: The majority of the country is contiguous, but also includes a small chain of tropical islands in the middle of the Pacific Ocean as well as a northern state which partially lies in the arctic circle. Canada lies to the north, and Mexico to the south, otherwise the country is bordered by ocean. On a global scale, the country is partially isolated from other powerful nations because of the oceans lying between it and the rest of the world. It has also acted as a barrier between the East and West, and have also taken advantage of this arrangement through trade.
The site of the United States is varied in its topology, climate and other characteristics. It consists of almost 4 million square miles in area. The eastern side of the country (bordered on the east by the Atlantic Ocean) consists of hardwood forests as well as high population density. In the north, the climate is humid and cold, to the south, humid and hot. There is a mountain range (the Appalachians) that runs from the north to the south parallel to the coastline. On the other side of these mountains lies forests and farmland, gradually merging with the Great Plains, an extensive, high altitude prairie that covers the entirety of the central area of the country north and south. These plains eventually reach the Rocky Mountains which extend from the northern to the southern border. On the western side of the Rockies lies various desert areas until another set of mountains are reached (the Sierra Nevada Range and the Cascade Range). These mountains parallel the western coast, and the land between the coast and the mountains are again covered in forests and greenery. To the north lies a separated portion of the country, which consists of mountainous areas of ice and cold. Far out in the ocean lies another portion of the county in the form of a small volcanic chain of tropical islands. The continental divide lies in the Rocky mountains, and many important rivers stem from these mountains.