The Maremma National Park contains various religious and military buildings of different historic periods, some of which are open to visitors. These include the Monastery of Santa Maria in Monte Alborensi, commonly known as San Rabano Abbey, dating back to the XI century. It was firstly run by the Benedectines, then by the Cistercians and finally by the Knights of the Holy Sepulchre of Jerusalem. There are several watchtowers, the most ancient of which is the Castelmarino tower, probably dating back to the XIII century. Another tower, the Uccellina tower, stands in the area of San Rabano Abbey. A typical Sienese tower of the early XVI century is the Collelungo tower. Another similar tower overlooks the beach Cala di Forno, after which the tower is named. Other interesting sights are the Bassa tower, the last remain of the Colecchio Castle and the Bella Marsilia Tower. The park encompasses also some archaeological sites, such as the cave “La Fabbrica” (Middle Lower Paleolithic), the cave of Spaccasasso (Eneolithic), the cave of Scoglietto (Early Bronze Age) and recent excavations in the villages of Scoglietto and Spolverino, dating back to the Roman Age.