Cerro del Hierro, Natural monument in Sierra Norte de Sevilla, Spain.

Cerro del Hierro is a hill and natural monument at 689 m in the Sierra Norte de Sevilla, about 5 km south of San Nicolás del Puerto. Its limestone, formed from Cambrian marine reefs and sponges, holds iron oxides and hydroxides in cavities. Open-pit mining has reshaped the relief, leaving tunnels that once carried ore wagons.

Iron mining at this site began during Roman times and continued through the centuries. In the 1800s, the Scottish company William Baird Mining took over operations and shaped the landscape as it appears today until activities declined mid-20th century.

The name refers to the iron deposits that shaped this landscape for centuries through extraction activities. Today, visitors can observe how mining left its mark on the terrain and the way people interact with this transformed natural space.

This site offers over 120 climbing routes of different difficulty levels and serves as the main climbing destination in Sevilla province. Wear sturdy footwear and watch for uneven paths and cave openings that appear suddenly throughout the landscape.

The iron from Cerro del Hierro was used to forge the railings on the facades of the Real Fábrica de Tabacos (now the University of Seville) and the structure of the Isabel II Bridge (Triana Bridge) over the Guadalquivir. A 15.1 km railway branch, opened in May 1895, linked the mining village to the Seville-Mérida line to transport the ore to the port of Seville.