Chaco, officially the Province of Chaco, is one of the 23 provinces in Argentina. Its capital and largest city, is Resistencia. It is located in the north-east of the country. It is bordered by Salta and Santiago del Estero to the west, Formosa to the north, Corrientes to the east, and Santa Fe to the south. It also has an international border with the Paraguayan Department of Ñeembucú.