 Campiglia Marittima is situated in the Upper Maremma region, near the river Cornia, an intermittent watercourse which gives its name to the area Campiglia belongs to, the so-called Val di Cornia.The bounding municipalities are Piombino, San Vincenzo and Suvereto.The "comune" includes the "frazioni" of Cafaggio and Venturina Terme, and the small hamlets of Banditelle and Lumiere.