Siega Verde Monument · Castillejo de Martín Viejo, Ciudad Rodrigo, Salamanca An open-air complex of Palaeolithic rock art along the river Águeda, in the area around Castillejo de Martín Viejo, Villar de Argañán and Villar de la Yegua (Ciudad Rodrigo), discovered on 17 October 1988 by Manuel Santonja, then director of the Museum of Salamanca, thanks to a local shepherd. It brings together more than 500 engravings, made by pecking, incision and abrasion, across 96 panels along one kilometre; they depict mostly horses, aurochs, deer and goats, along with rarer animals such as reindeer, woolly rhinoceros or bison, now extinct at these latitudes. They date between the Gravettian-Solutrean, around 20,000 years ago, and the Magdalenian, 17,000-9,000 years ago. A Bien de Interés Cultural (Spain's highest level of heritage protection) since 1998, Unesco added it in 2010 to the World Heritage list. Photo: Vanbasten 23 (CC0) What to see and do in Castillejo de Martín Viejo