Black truffle of the sierra's holm oak woods Food and drink · Monterde de Albarracín, Sierra de Albarracín, Teruel The limestone holm oak woods of the sierra produce black winter truffle, sought with a dog between December and March. To the wild gathering have been added truffle plantations that bring income to the smallest municipalities. Photo: Diego Delso (CC BY-SA 3.0) What to see and do in Monterde de Albarracín