Gate of Carlos IV and the aludel kilns Monument · Almadén, Valle de Alcudia, Ciudad Real Image of Almadén, not of the place itself. The outer ensemble of the mining compound, made up of the monumental Carlos IV gateway and the 17th-century aludel furnaces used to distil cinnabar and obtain mercury. Photo: Miguel Calvo (CC BY 4.0) What to see and do in Almadén