Fuerte de San Miguel is a military fortification in the small town of Dieciocho de Julio in the Rocha Department of eastern Uruguay. It was erected in 1737 by the Portuguese, having abandoned the attempt at building a fort in Maldonado. It was constructed of large, heavy stones to create the tall towers thick walls and sturdy ramparts to withstand the onslaught of wars fought against the Spanish invaders which was instrumental in Uruguay evolving as an independent nation.