Steelmaking ranks as the most important industrial activity.  Steel mills use ore brought by lake freighters from Michigan and Minnesota.  They produce over 13,000,000 tons of steel ingots and castings a year.  The steel industry centers in the Calumet region, made up of East Chicago, Hammond, Whiting, and Gary.  One of the world's largest steel mills is in Gary.  Indiana also manufactures electrical machinery, foundry products, pumps, railway equipment, rubber products, hosiery, leather products, drugs, glass products, pottery, cotton, woolen cloth, and clothing.