Dating back to the twelfth century, was one of two ports of representation (the other was the Gate of Parlascio), ie those particular city gates through which the people were made to pass from that period. In particular, this led directly to the religious center of the city and a symbol of his power. The name is due to the lion in marble, probably of Etruscan origin placed outside in a niche, as a protector of the city. After the occupation of the Florentine lion was moved over the walls facing within the city itself, not as overseer of Pisa, but as if it was to watch over the city itself.