Lac à Castor is a Lake located in Côte-Nord-du-Golfe-du-Saint-Laurent; Basse-Côte-Nord, Quebec.

• Latitude: 50° 16' 44'' North   (decimal: 50.2789581)
• Longitude: 61° 10' 53'' West   (decimal: -61.1814554)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Location: Côte-Nord-du-Golfe-du-Saint-Laurent; Basse-Côte-Nord
• Atlas of Canada Locator Map: Lac à Castor
• GPS Coordinate Locator Map: Lac à Castor Lat/Long