Messac is a former commune in the Ille-et-Vilaine department of Brittany in northwestern France. On 1 January 2016, it was merged into the new commune Guipry-Messac.
Wikipedia https://en.wikipedia.org/wiki/Messac,_Ille-et-Vilaine
Coordinates 47°49'29.844" N -1°48'19.682" E