Forte on Mount Campolongo: A Modern Marmot's Lair, Battled and Broken by the

Situated at 1,720 meters, knee-deep in the Vicenza-Trentino frontier, this fortress sported four 149mm cannons, four 75mm cannons, and four machine guns, making it one of the most cutting-edge construction projects under the Italian Military Engineer. The fortress, however, tasted the taste of battle in July 1915 and suffered significant damage. On May 15, 1916, it was reduced to ruins. The enemy occupied it on May 22, 1916 and held it until the war ended. Now, it's been refurbished and can be reached through the Campolongo refuge or the Spiazzo Garibaldi.

Sources: Wikipedia, OpenStreetMap, Wikidata, Wikimedia Commons