Lac-Sébastien is a Unincorporated area located in Saint-David-de-Falardeau; Le Fjord-du-Saguenay, Quebec and has an elevation of 181 meters.

• Latitude: 48° 38' 36'' North   (decimal: 48.6433333)
• Longitude: 71° 7' 36'' West   (decimal: -71.1266667)
• Topography Feature Category: Unincorporated area
• Geographical Feature: Hameau
• Canadian Province/Territory: Quebec
• Elevation: 181 meters
• Location: Saint-David-de-Falardeau; Le Fjord-du-Saguenay
• Atlas of Canada Locator Map: Lac-Sébastien
• GPS Coordinate Locator Map: Lac-Sébastien Lat/Long