Archaeological excavations at the site of Dessobriga in Osorno la Mayor (province of Palencia, Castile and León). East gate to Dessobriga. At the bottom of the Valley, parallel to the river Valdavia elapses the autovía de Santiago or A-231, old via Asturica-Tarracone where Dessobriga is mentioned in the itinerary of Antoninus (449, 4) as a mansio among the mansions of Lacóbriga and Segisamone, which is separate XV miles on both occasions.