Fierro is an archaic form of hierro, the Spanish word for “iron,” and iron is the reason the town was born in the first place. The mining history goes back to 1841, when Sofio Henkle, a German immigrant living in Mexico, went looking for copper deposits. He found both copper and iron on a mountain a few miles north of the big copper mine in Santa Rita. The drilling frame still stands, and the safe lies locked in what is left of the mining company's office.
The population of Fierro was 750 in 1920 and probably never much over 1,000, even during the peak years between WWI and the start of the Great Depression, by which point six million tons of iron had come from Fierro’s mines.
Virtually no one lives here anymore, and the buildings stand empty. The townsite is marked as "historic."
The old train tracks likewise wait, in hope that life might return someday.