Monte Argentario, in southern Tuscany, was an island in ancient times. Because of the debris carried by the Albegna River and the extensive sea current, it then joined the Tyrrhenian Coast with two strips of land, creating the tomboli (dunes) of Feniglia and Giannella, and leading to the birth of the Lagoon of Orbetello.

The promontory overlooks the Tyrrhenian Sea on the side of the more southern islands in the Tuscan Archipelago, Giglio and Giannutri. The indented coast offers bays and small inlets, with sandy beaches and mostly pebble beaches, beautiful from a naturalistic point of view.

The Municipality of Monte Argentario is made of two sea towns: Porto Santo Stefano in the North and the smaller Porto Ercole in the South.