Lac Impossible is a Lake located in Lac-Lenôtre; La Vallée-de-la-Gatineau, Quebec.

• Latitude: 47° 32' 41'' North   (decimal: 47.5447930)
• Longitude: 75° 49' 43'' West   (decimal: -75.8285280)
• Topography Feature Category: Lake
• Geographical Feature: Lac
• Canadian Province/Territory: Quebec
• Location: Lac-Lenôtre; La Vallée-de-la-Gatineau
• Atlas of Canada Locator Map: Lac Impossible
• GPS Coordinate Locator Map: Lac Impossible Lat/Long