Lac des Joncs is a Lake located in Saint-Alexis-des-Monts; Maskinongé, Quebec and has an elevation of 405 meters.

• Latitude: 46° 44' 59'' North   (decimal: 46.7497560)
• Longitude: 73° 22' 53'' West   (decimal: -73.3815222)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Elevation: 405 meters
• Location: Saint-Alexis-des-Monts; Maskinongé
• Atlas of Canada Locator Map: Lac des Joncs
• GPS Coordinate Locator Map: Lac des Joncs Lat/Long