San Justo is a city in the center region of the province of Santa Fe, Argentina, 99 km north from the provincial capital. It had about 22,000 inhabitants at the and it is the head town of the San Justo Department. Founded in 1868 by Mariano Cabal, San Justo attained the status of a comuna (commune) on 13 July 1887 and the following year the Ferrocarril Provincial de Santa Fe arrived on 1 September 1888. It became a city on 17 September 1959. On January 10, 1973, the town was struck by a destructive tornado.