Bourg, also informally known as Bourg-sur-Gironde, is a commune in the Gironde department in Nouvelle-Aquitaine in southwestern France. It …Bourg, also informally known as Bourg-sur-Gironde, is a commune in the Gironde department in Nouvelle-Aquitaine in southwestern France. It is part of the Côtes de Bourg wine region. Bourg originated as a fortified villa built by the Roman prefect Pontius Paulinus in the 4th century.