The fort of the Brunetta stood on the height of that name, a spur of rock bared by glacial erosion that overlooks Susa from the north, between the Dora Riparia and the Cenischia. Work began in 1708, when the Duchy of Savoy decided to strengthen its border fortifications after the War of the Spanish Succession had shown their worth, and the fort was delivered some thirty years after the first stone. The design was by the Savoy engineer Antonio Bertola.
What to see
It was not a fort but a military citadel: it covered more than three hundred thousand square metres and held a church, barracks and a hospital. The five bastions were called San Pietro, San Lazzaro, San Maurizio, Sant'Antonio and Santa Maria, and were carved directly into the living rock: they were therefore held able to withstand the artillery of the day, and the structure passed for impregnable. The works also absorbed the old fort of Santa Maria, by then ruined after many wars, and the Catinat redoubt, which watched from above the mouth of the Val Cenischia and so the road to the Mont Cenis.
Visiting
The position explains everything: Susa sits at the crossing of the roads to two decisive passes, the Mont Cenis towards Savoy and northern France, the Montgenèvre towards the Dauphiné and southern France. Whoever held the Brunetta held the way into Italy on that side. It drew distinguished visitors: the emperor Joseph II in 1769, and tsar Paul I, who stayed there in 1791; both were genuinely astonished by it.
Our editors' tip
The Brunetta never fired a shot, and that may be the measure of its success: in 1747 the French, rather than face it, tried to cross the watershed by the Colle dell'Assietta, where the battle of that name was fought, and in the Napoleonic campaigns they chose the Great St Bernard. In 1796 Napoleon, having defeated the Kingdom of Sardinia, imposed by the armistice of Cherasco the destruction of all the kingdom's fortifications, and the Brunetta was dismantled. With the Restoration the destroyed forts were rebuilt, but not this one: Napoleon had made the Mont Cenis road carriageable on a route that passed above the citadel, so a barrier now had to stand higher up. In its place the forts of the Esseillon were built.