The United States of America is the world's third or fourth largest country by total area, located primarily in North America. It consists of 48 contiguous states, the state of Alaska in the northwest, and the island state of Hawaii in the Pacific. Washington, D.C. is the capital. A major geographical feature is the Continental Divide, a mountain ridge that follows the crests of the Rocky Mountains and separates the watersheds that drain into the Pacific Ocean from those that drain into the Atlantic and Arctic Oceans. The U.S. features diverse landscapes, including the Great Plains, the Appalachian Mountains, the Mississippi River system, and the arid deserts of the Southwest. Death Valley in California is the lowest and hottest point in North America. The country experiences a wide range of climates, from tropical in Florida and Hawaii to arctic in Alaska. It is home to the world's first national park, Yellowstone, established in 1872.