 The abbey at San Pietro Avellano was abandoned after a devastating earthquake in 1441, but the village remained an ecclesiastical dependency of Monte Cassino until 1785.The municipality of San Pietro Avellana contains the "frazione" (subdivision) Masserie di Cristo.San Pietro Avellana borders municipalities Ateleta, Capracotta, Castel del Giudice, Castel di Sangro, Roccaraso and Vastogirardi.