Patagonia is a region located at the southern end of South America, shared by Argentina and Chile. The region comprises the southern section of the Andes mountains as well as the deserts, steppes and grasslands east of this southern portion of the Andes. The Colorado River is usually considered its northern boundary in Argentine territory. To the west, it includes the territory of Valdivia through Tierra del Fuego archipelago. Patagonia has two coasts; a western one towards the Pacific Ocean and an eastern one towards the Atlantic Ocean.