The ethnographic museum of resin Monument · Casillas, Arenas de San Pedro, Ávila Image of Casillas, not of the place itself. The La Resina room brings together tools, pots and testimonies of the trade that for decades gave work to much of the local population, when the pine woods of the municipality were tapped each spring to extract the resin. Photo: Asqueladd (CC BY-SA 3.0) What to see and do in Casillas