On the eastern side of the New Walls, immediately after the Castellaccio, is the Porta delle Chiappe (or S. Simone). Brusco’s survey (table no. 29 – VIII) indicated the route of a “road leading to the Baracca del Puin, to the Torrazza and to Croce d’Orero”.
This road began on the side of a trapezoidal enclosure, outside the walls, and continued along the moat, almost as far as the Sperone. On the other side, inside the walls, the gate opened onto a small triangular-shaped square where two roads joined up: one that descended steeply to the ancient Porta Carbonara next to the Abergo dei Poveri, and another, longer and with a gentler descent, that reached the bastion of S. Giorgio to the west of the “Vecchie Mura” and then entered the city through the Porta S. Tommaso. The wide vaulted gallery that ran across the rampart from one end to the other narrowed towards the outer gate, leaving space on either side for two small barracks with embrasures for the sentries. The entire floor above the gallery was occupied by a quarter” for the guards, which included a rectangular garrison projecting over the parapet of the wall, and towards the inside a hallway, a dormitory and a kitchen.
Originally, as Codeviola’s drawings clearly indicate, the outer gate of San Simone did not have a drawbridge, but a simple wooden ramp, set up as a footbridge leading to the outer square; in the subsequent transformations of the 19th century, the entire floor of the gallery was lowered by about 1.30 metres and consequently the arches of the two extreme portals were lowered. On the outer one, framed by a stone arch, a drawbridge was placed, of which only the holes for the passage of the lifting chains remain. The two jambs of the gate were reinforced by two brick pilasters that rose vertically up to the brackets of the sentry box. Finally, the entire upper floor was demolished and levelled to allow the passage of the military road, which had to continue uninterrupted along the Bisagno ramparts as far as the Sperone.
(Taken from “Le Fortificazioni di Genova” by Leone Carlo Forti)