The royal glass and steel factories Historical milestone · Utrillas, Cuencas Mineras, Teruel Image of Utrillas, not of the place itself. In 1798, under the reign of Carlos III, two royal factories devoted to glass and steel were installed in the district, taking advantage of the local coal. Production was maintained until 1822, when both manufactures ceased their activity. 1798-1822 Photo: sergioski1982 (CC BY-SA 2.0) What to see and do in Utrillas