Lac du Sommeil is a Lake located in Mont-Valin; Le Fjord-du-Saguenay, Quebec.

• Latitude: 48° 56' 5'' North   (decimal: 48.9347634)
• Longitude: 70° 57' 0'' West   (decimal: -70.9500770)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Location: Mont-Valin; Le Fjord-du-Saguenay
• Atlas of Canada Locator Map: Lac du Sommeil
• GPS Coordinate Locator Map: Lac du Sommeil Lat/Long