This was the second entrance of the castle, of lesser importance, as it faced a sparsely populated agricultural area.
It was precisely the rural district outside the castle, called "Cerva," that ended up giving its name to the tower and the door.
Due to the low traffic at this door, it was even closed off with a wall in the 14th century. Having lost its military purpose over the centuries, in 1876 it was raised by the parish to accommodate six large bells and thus became the bell tower of the religious community.
