Argentina is located in southern South America and has a total area of approximately 1,500,000 sq. miles– including the mainland and the Argentine Antarctica and South Atlantic Islands. It is the eight largest country in the world, nearly the size of that part of the United States east of the Mississippi River. Topography and climate vary significantly, with the high Andes mountain in the west, subtropical climate in the northeast, temperate climate in the middle part of the country, and semi-arid and cold in the southern part. The middle third of the country, which includes Buenos Aires, contains the greatest part of the population, as well as most of the economic activity and agricultural production.