Fortress of Civitella del Tronto

The Fortezza di Civitella del Tronto, a fortress in Civitella del Tronto, Province of Teramo (Abruzzo), Italy, stands as a testament to the strategic importance of this area in Italy's history. Built in the 11th century during the Swabian period, the fortress was further fortified under the Angevins, who added circular flanking towers at the corners and along the straight walls. The fortress it's one of the most visited monuments in Abruzzo, with 45,000 annual visitors (2016 data). One of the most famous events that took place inside the fortress was the siege and eventual surrender of the fortress to the Piedmontese on March 20, 1861, three days after the coronation of King Vittorio Emanuele II.

Sources: Wikipedia, OpenStreetMap, Wikidata, Wikimedia Commons