The black truffle of Villaciervos Food and drink · Villaciervos, Frentes, Soria Alongside the traditional wheat, barley and rye, the municipality today has some six hundred hectares of mycorrhized holm oaks intended for the production of black truffle, the crop that has renewed its farming economy. Photo: Diego Delso (CC BY-SA 3.0) What to see and do in Villaciervos