SAN JUAN, an Andean province of Argentina, bounded north and east by La Rioja, south by San Luis and Mendoza, and west by Chile, from which it is separated by the Andean Cordilleras. Area, sq•m• ; pop. (1934, estimate) 189483. It is roughly mountainous, and belongs to the closed drainage basin of western Argentina, centring in the province of Mendoza. It is traversed by several rivers, fed by the melting snows of the Andes and dis charging into the swamps and lagoons in the south-eastern part of the province, the largest of which are the Huanacache lagoons. The largest of these rivers are the Vermejo, Zanj6n or Jachal and San Juan. They are all used for irrigation. The climate is ex tremely hot and dry in summer, but the winter temperature is mild and pleasant. Agriculture is the principal occupation of its inhabitants, though the soil is generally sterile and the rainfall uncertain and very light. Cereals are grown in some localities, and there are large vineyards where irrigation is possible, from which excellent wine is made. The province contains gold, silver, copper, iron, lead, coal and salt, but mining has never been de veloped to any extent. Pastoral interests are largely in feeding cattle for the Chilean markets, for which large areas of alfalfa are grown in the irrigated valleys of the Andes. The Argentine Great Western railway connects the capital of the province with Mendoza, and thus with the other principal cities of the republic.
The capital of the province is San Juan, once called San Juan de la Frontera (pop., 1914, 16,631), in a great bend of the San
Juan river, 95 m. N. of Mendoza and 73o m. from Buenos Aires by rail. The great bend of the river affords easy irrigation, and the surrounding country is covered by a network of irrigating canals, even the paved streets of the town having streams of cool water running through them. The public buildings include a cathedral, three churches and several schools, including the "Escuela Sarmiento," a fine edifice with a Greek façade, named after President Domingo Faustino Sarmiento (i811-86), who was a native of this city. There is also a botanical garden.
San Juan was founded in 1561 by Juan Yufre, a companion of Captain Castillo, the founder of Mendoza. Both came from Chile, to which these outlying colonies were at first subject. From 1776 to 182o it was governed from Mendoza, and then a popular upris ing made the province independent and the town its capital. It has suffered severely from political disorders, and in 1894 was nearly destroyed by an earthquake. The original settlement, now called Pueblo Viejo, 4 m. N., was abandoned on account of fre quent inundations. The present town is situated about 2,165 ft. above sea-level and is defended from inundations by an embank ment above the town, called the MurallOn. San Juan exports wine, and has trade with Chile over the Patos and Uspallata passes.