Molac is a commune in the Morbihan department of Brittany in north-western France. The river Arz forms most of the commune's south-w…Molac is a commune in the Morbihan department of Brittany in north-western France. The river Arz forms most of the commune's south-western border, then flows eastward through the south-eastern part of the commune. Molac is located in the heart of a forest-covered region called in French the Landes de Lanvaux. The village centre is located 25 km east of Vannes.