The Andes, Andes Mountains or Andean Mountain Range are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is 8,900 km long and 200 to 700 km wide and has an average height of about 4,000 m. The Andes extend from South to North through seven South American co…The Andes, Andes Mountains or Andean Mountain Range are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is 8,900 km long and 200 to 700 km wide and has an average height of about 4,000 m. The Andes extend from South to North through seven South American countries: Argentina, Chile, Bolivia, Peru, Ecuador, Colombia, and Venezuela.