The Americas comprise territories in North, Central and South America. There are a total of 35 countries located across the three regions. North America has 23 countries and is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the east and west, and South America to the south. It includes three major physical regions - the Rocky Mountains, Great Lakes, and Mississippi River. South America has 12 countries and is located in the Southern Hemisphere, bordered by the Atlantic Ocean to the east and west, the Caribbean Sea to the northwest, and North America to the north. It is home to the Andes Mountains and Amazon Rainforest.