The first blast furnaces of the peninsula Historical milestone · Sabero, La Montaña de Riaño, León Image of Sabero, not of the place itself. In 1847 the San Blas ironworks housed the first blast furnaces to come into operation on the Iberian peninsula, a pioneering attempt at modern iron and steel making that soon died out for lack of transport infrastructure. 1847 Photo: David Perez (CC BY 3.0) What to see and do in Sabero