San Juan (săn wän, Span. sän hwän) [key], city (1991 pop. 353,476), capital of San Juan prov., W Argentina. It is a commercial and industrial center in an agricultural region. Wine is the chief product, and vineyards dot the picturesque landscape. Fruits and grains are grown, cattle are raised, and the province is rich in minerals. Founded in 1562, San Juan figured prominently in the civil wars of the 19th cent. Many Argentine statesmen, including Domingo Faustino Sarmiento, were born in San Juan.