Saint-Marceau () is a commune in the Sarthe department in the region of Pays de la Loire in north-western France.
After the liberation of the area by Allied Forces in August 1944, engineers of the Ninth Air Force IX Engineering Command began construction of a combat Advanced Landing Ground outside of the town. Declared operational on 31 August, the airfield was designated as "A-43". It was used by several combat units until November 1944 when the units moved to Central France and the airfield was closed.