Santiago del Estero, city (1991 pop. including La Banda 264,273), capital of Santiago del Estero prov., N Argentina. It is a transportation hub of the Argentine Chaco and a commercial center for cattle raised in the region. Founded in 1553, Santiago del Estero is one of the oldest cities of Argentina. Nearby thermal springs have made the city a health resort. There are two 16th-century churches.