Flour mill of Urrea de Gaén Monument · Urrea de Gaén, Bajo Martín, Teruel Image of Urrea de Gaén, not of the place itself. The flour mill of Urrea de Gaén, commissioned by the dukes of Híjar beside the river Martín, is today practically in ruins; it had two floors, with the milling area below and the miller's dwelling above. Photo: Juan Emilio Prades Bel (CC BY 4.0) What to see and do in Urrea de Gaén