a town of France in the department of Morbihan, on the peninsula of Ruis, which forms the south shore of the bay of Morbihan, 14 miles S. of Vannes. The principal building is a church with a lofty tower; and another object, so conspicuous as to form a sea-mark for coasting vessels, is a high conical tumulus, the largest in France. The town is chiefly inhabited by sailors, and has some trade in salt and in the indifferent wine of the vicinity. Sarzeau was the birthplace of Le Sage, the well-known author of *Gil Blas*. Pop. 7425.