The fort is at the center of four protected areas: Majella National Park, Sirente Velino Regional Park, Gran Sasso National Park and League Mountains, National Park of Abruzzo, Lazio and Molise. The first populated area of the Rocca dates back to the Middle Paleolithic (100,000 - 40,000 years ago). Around 300 BC Rocca Calascio fell under Roman jurisdiction, to the dependencies of the Town Hall of Peltuinium (current Ansidonia). The Rocca Calascio Tower, located on a promontory with wide view of the valley, created an optical network with other towers. In Roman times the site was used as a sighting point to control the entire area, thanks to the use of a wooden tower. The oldest construction element is the square-based tower dating to the beginning of the 11th century. The tower has a perfectly square plant (18x18 meters), with four circular turrets and a square-shaped doorman (10x10 meters). The latter has the stem executed with two different types of masonry: the lower (the oldest) area, developed at an altitude of 8 meters, is made with large square blocks (Opus Quadratum) and can be dated around 1000 - 1200, while the overhanging part, slightly recessed, is made of a stone masonry combined with a lot of mortar and arranged according to the Opus Aquilanum (Opus Incertum) technique. Originally the tower consisted of three floors and a terrace for sighting: it had an underground cistern for the supply of rainwater that, by wells, could be picked up on the first floor. The opening on the ground floor, from which is now accessed to the Tower, was recently excavated, following the renovation work in 1989. Originally, the Rocca had entry into the existing first floor window with which it came with a ladder inside; even the bridge was retractable. By the middle of the 15th century Antonio Piccolomini adapted the tower to the new techniques of war, with the realization of the rifles, the four cylindrical towers and the wall of the town around the village. In addition, he rebuilt the plans above the first, collapsed after the disastrous earthquake of 1451. Following the 1703 earthquake, the Rocca was no longer rebuilt. The Tower is very famous for being the location of some internationally renowned films such as King David (1985, with Richard Gere), Lady Hawke (1985, with Michelle Pfeiffer) and The American (2010, with George Clooney).