The Montioni Interprovincial Park is a protected natural area covering about 7 thousand hectares straddling the towns of Follonica, Massa Marittima, Suvereto, Piombino and Campiglia Marittima.
The territory is characterized by the presence of historical and artistic evidence: from the remains of protohistoric settlements, to Etruscan and Roman ones overlaid by medieval buildings such as the Pievaccia, the ruins of the Old Montioni Castle, the Montioni Baths and various testimonies of medieval archaeology such as the alum quarries. Within the perimeter of the park is the Poggio Tre Cancelli State Nature Reserve.
The hills of Montioni Park are covered with dense native vegetation, where holm oaks but also conifers prevail. The fauna is represented by various wild species typical of the area: ornithics and ungulates, such as roe deer and wild boar, abound.