Parco Naturale del Gran Bosco di Salbertrand

It is a structure entirely surrounded by a large ditch developing on two levels. From the yard in front of it, a bridge partly fixed and partly drawbridge used to cross the deep ditch to lead, across the sober portal, inside the fort on the entrance atrium.
In 1882, Italy was part of the Triple Alliance (Germany, Italy, and Austria), and the neighboring France, belonging to the Triple Entente (France, England, and Russia) had become its direct potential enemy. For the defense of that stretch of terrestrial border, as strong point of Piazza di Exilles, they decided to use the pre-existing fort, adapting it to the great technical progresses made in the field of artillery. As a matter of fact, cannon rifling had revolutionized the military techniques and greatly increased the ball range. In order to resist the rifled artillery, the forts with ditch were born (a big hole protected by packed-earth embankments). The fortress was built in this hole, like the Fort Sapè. With this kind of fortresses, the fortified system called "entrenched field" gained ground: its strong point was represented by a fort armed with big artillery (in our case, the renovated fortification of Exilles, the Main Fort), protected by several secondary structures which, for the Piazza di Exilles, should have been seven: Sapè, Fenil, Case Garde, Serra la Garde, Clot Riond, Val Galambra, and Icharette, but which were limited to four, since the last three structures were never built. The function of these complementary structures was to keep at bay, with their own fittings, the field artillery of the enemy, which could be attacked by the main fort with the fire of its long-range big artillery.
Fort Sapè, planned in 1884 by the Captain of the Corps of Engineers Darbesio, was completed in 1886 and definitively abandoned in 1928.