Celtiberian tower of San Cristóbal Monument · Anento, Campo de Daroca, Zaragoza Above the site of the Aguallueve stands a Celtiberian tower dated to around the year 200 before Christ. Its dominant position over the ravine documents the pre-Roman settlement of the sierra before the medieval organisation of the territory. siglo II a. C. Photo: José M. Ciordia (CC BY-SA 4.0) What to see and do in Anento