Festivities of invierno de Tierga Activity · Tierga, Aranda, Zaragoza Image of Tierga, not of the place itself. Tierga's winter festival is held in a village south of the Moncayo whose flocks of sheep, raised on scrubland and high pastures, produce the ternasco covered by the Ternasco de Aragón Protected Geographical Indication. Photo: Ecelan (CC BY-SA 4.0) What to see and do in Tierga