The Porta Viridaria is one of the oldest gates in the walls surrounding the Vatican. It opens into Leonine City, or the Borgo, an independent municipality that sits at the entrance to the Vatican. Both were encolosed by the Leonine Walls in 852 to defend against invaders.
- The Porta Viridaria has had many other names including Porta San Petri, Porta di Belvedere, Porta San Pellegrino, Porta Palatina, Porta Aurea and Porta San Peregrini. This is referred to in its database entry by Shaun Hastings.