In the layout of the 16th century Walls, the Baluardo San Giorgio, located between the valleys of Sant’Ugo and San Tomaso and raised to 111 metres above sea level on a slope of the Peralto hill, was one of the western cornerstones of the city walls; with its orthogonal salient with a rounded edge and powerful sides with an accentuated scarp, it reveals the peculiar characteristics of 16th century military architecture expressed in Genoa by Olgiati. The clustering of buildings prevents a perspective view, however, from salita Oregina, it is possible to see the imposing western side, which ends with an auricle outside the 19th century building and superimposed on the bulwark.
Garrisoned at the beginning of the 17th century by a garrison of German mercenaries, in 1624, at the first signs of war, it was equipped with a few pieces of artillery and the garrison was adequately reinforced.
In 1746, it was a centre of resistance for the Austrians who had barricaded themselves there, and later a post for the insurgents against the Imperials gathered at the Porta di San Tomaso.
On the parapet of that bastioned perimeter, a fortified structure was built according to a project by the Piedmontese Military Engineers. Built between 1818 and 1828, the Fort was located in a position dominating the Port and the western part of the City, and offered ample opportunity to intervene in the event of any uprising; at a closer distance, it also guaranteed the defence of the Arsenale di Terra below (formerly the Convent of the Spirito Santo) where the arms and artillery stores were centralised.
The building, with a trapezoidal plan and four floors, was enclosed within an enclosure and had access through a large arched doorway located in the curtain wall descending towards Montegalletto, where the Portello di Sant’Ugo probably already existed.
Considered by the Genoese as a permanent threat to their libertarian aspirations, like the Castelletto, in 1848, during a popular uprising, the Fort was stormed and demolished. The building, rebuilt in the last century, houses the Observatory and the Hydrographic Institute of the Navy.
Translated with www.DeepL.com/Translator (free version)
(Taken from “Mura e Fortificazioni di Genova” Riccardo Dellepiane, Nuova Editrice Genovese)