The Midwest US is one of four geographic regions defined by the US Census Bureau. It occupies the north central part of the USA. It borders the Northeastern US, the Western US, the Southern US, and Canada to the north. It generally lies on the Interior Plain between the Appalachian Mountains and the Rocky Mountains. It includes a large portion of the Great Lakes Region and the Great Plains. Major rivers include the Mississippi River, Ohio River, and Missouri River. Agriculture is the primary economic driver followed by industry, mining, and trade.