The article describes the development and characteristics of the production of steel in the Basque Country. Iron could be obtained in three ways: smelting, steel and iron. Iron seems to date back to 3000 B.C., and it arrived in the Iberian peninsula towards 650 B.C. One of the first ironsmitheries was that in Peñas de Aya (Gipuzkoa). In the development of Basque siderurgy there are two stages: the classical one with two different periods (mountain and river bank smitheries) and modern age