Margaux is a former commune in the Gironde department in Nouvelle-Aquitaine in southwestern France. On 1 January 2017, it was merge…Margaux is a former commune in the Gironde department in Nouvelle-Aquitaine in southwestern France. On 1 January 2017, it was merged into the new commune Margaux-Cantenac. The village lies in the Haut Médoc wine making region on the left bank of the Garonne estuary, northwest of the city of Bordeaux.