Forte delle Marze, Coastal fort in Grosseto, Italy.

Forte delle Marze is a coastal fortification at the north-western edge of Grosseto's municipal territory, on the shore between Marina di Grosseto and Castiglione della Pescaia. It has a quadrangular plan, with stone-clad walls at the lower levels and brickwork above. A 20th-century renovation turned it into a holiday villa: the highest block carries a shallow four-pitched roof with a row of chimneys, and a 20th-century loggia with a pitched roof stands over the terrace enclosed by the western curtain wall.

The Lorena dynasty built the fort in the second half of the 18th century, probably on the site of an earlier fortification. Besides watching and defending the coast, it collected salt after the old salt pans near the Torre della Trappola closed and served as a base for Leonardo Ximenes's land-reclamation works. It was used only for military purposes from the late 18th to the mid-19th century, then definitively disarmed.

The fort's name comes from the Marze area at the north-western edge of Grosseto's municipal territory, on the coastal stretch between Marina di Grosseto and Castiglione della Pescaia. After the historic salt pans near the Torre della Trappola were abandoned, the complex became a salt collection point, and it also served as a base for the land reclamation works directed by Leonardo Ximenes. The 20th-century renovation turned it into a holiday house, so it now looks like a villa rather than a military post.

The fort stands at the start of the beach, at the north-western edge of Grosseto's municipal territory, on the coastal stretch between Marina di Grosseto and Castiglione della Pescaia. The shoreline has retreated since it was built, so the building no longer sits directly on the water. Approach on foot along the beach; the ground around it is flat.

The fort's lower walls are clad in stone and its upper levels in brick, a two-material construction that survives from the original building beneath the 20th-century villa conversion. Look for the scarped stone curtains and the tall block with its four low-pitched slopes and row of chimneys.