In Piazzale Labicano, on the outer face of the Aurelian Wall, to the left of Porta Maggiore, is a marble plaque commemorating the restoration undertaken by Pope Gregory XVI (1831-1846) in the tenth year of his pontificate. The work was for defensive purposes, and cumbersome and superfluous later additions were removed from the Aurelian gate, such as the narrowing of the archways and the erection of a crenelated wall, which was removed in 1915 during work carried out on the area by the Municipality of Rome. The appearance of the gate, prior to the 19th century transformations, is rendered by historical graphic representations, including the famous engravings by Giovanni Battista Piranesi and Giuseppe Vasi.
The plaque with a barely legible inscription originally bore the following text: S.P.Q.R./QUI TRASFERITA DALLA VICINA PORTA PRENESTINA/RESTITUENDO ALL’ANTICA FORMA/I FORNICI DI CLAUDIO/MCMXVI.
On the same occasion, Gregory XVI had a second plaque affixed in honour of the emperors Arcadius and Honorius, who at the beginning of the 5th century had rebuilt the gate in its present location, preserving the foundations of the previous structure. The plaque with the inscription inscribed in black, is located in Piazzale Labicano, embedded in the section of the Aurelian Wall to the left of Porta Maggiore at a height of about 65 centimetres from the ground.
2. Plaque Gregory XVI (1836-1840)