Lac Castonguay is a Lake located in Senneterre; Vallée-de-l'Or, Quebec and has an elevation of 390 meters.

• Latitude: 48° 50' 55'' North   (decimal: 48.8486111)
• Longitude: 76° 26' 5'' West   (decimal: -76.4347221)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Elevation: 390 meters
• Location: Senneterre; Vallée-de-l'Or
• Atlas of Canada Locator Map: Lac Castonguay
• GPS Coordinate Locator Map: Lac Castonguay Lat/Long