Patagonia (pätägōˈnyä) [key], region, c.300,000 sq mi (777,000 sq km), primarily in S Argentina, S of the Río Colorado and E of the Andes, but including extreme SE Chile and N Tierra del Fuego. Patagonia, except for the far southern plains, the sub-Andean region, and the Andes, is a vast, wind-swept semiarid plateau, sloping gently toward the east and terminating in cliffs along the Atlantic Ocean. Crossing from the Andes to the Atlantic are transverse valleys, some cradling rivers. Although most of the water courses are intermittently dry, some rivers (the Río Negro, the Chubut, the Santa Cruz, and the Gallegos) are perennial. The sub-Andean region in the west contains numerous lakes (Nahuel Huapí, Buenos Aires, Viedma, and Argentino) fed by glaciers; it also has some deep, fertile valleys. Subantarctic conditions prevail in the far south. The region is at times affected by the eruption of Andean volcanoes; in 1991 an eruption of the Hudson Volcano in Chile caused great ecological damage in Patagonia.
Until recently sheep raising (mainly for wool) was the major industry of Patagonia, but oil production, particularly around Neuquen, Río Gallegos, and Comodoro Rivadavia (the region's largest city), has become very important. There are coal deposits in the upper Río Gallegos valley, and iron-ore deposits at Sierra Grande. Tourist resorts in the lake region are very popular. Cattle are raised, and agriculture is practiced in irrigated oases along the Río Negro and the Chubut. A rich field for the paleontologist, Patagonia has been visited by many scientific expeditions since the days of Charles Darwin. Of the original inhabitants, the Tehuelches (the "Patagonian giants") are the most important. Among the native animals are the guanaco, the rhea, the puma, and the deer.
Probably first visited (1501) by Amerigo Vespucci, the Patagonian coast was explored (1520) by Ferdinand Magellan. Settlements were attempted in the 16th and 17th cent., but the inhospitable country and natives discouraged colonization. It was not until after Julio A. Roca, an Argentine general, campaigned against the native people that Argentine ranchers began entering the territory in the late 19th cent. Chileans had been coming in for some time, and despite efforts to exclude them during and after the Argentine-Chilean boundary dispute in the early 20th cent., many continued to immigrate. Many Europeans, including many British, took up ranches, and immigration has made the population ethnically the most European in all Argentina.
Making up more than a third of Argentine territory and still sparsely populated, Patagonia is a vast natural reserve, and settlement has steadily increased. The region became fashionable with wealthy foreigners in the 1990s and many celebrities bought homes there, fueling a boom in property sales. Studies have revealed the presence of vast untapped mineral wealth. By the 1990s, environmental damage caused by the depletion of the ozone layer in the Antarctic region had become noticeable.
See W. H. Hudson, Idle Days in Patagonia (new ed. 1985).