In November 2013, during archaeological excavations and refurbishment, it was discovered a lion on the north wall of Castulo. The sculpture, made on a sandstone block weighs nearly a ton, and depicts a roaring lion, lying on its paws among which are a human figure. He remained for centuries guarding a door of an integrated wall monument outside the city.
This monument was located in the highest place of the wall of Castulo. The Romans had chosen a prominent place from which this monument would be seen long distance by those approaching the city.