Blackmarsh Gully is a Lake located in Harbour Main-Bell Island, Newfoundland and Labrador and has an elevation of 135 meters.

• Latitude: 47° 21' 43'' North   (decimal: 47.3619444)
• Longitude: 53° 22' 8'' West   (decimal: -53.3688888)
• Topography Feature Category: Lake
• Geographical Feature: Gully
• Canadian Province/Territory: Newfoundland and Labrador
• Elevation: 135 meters
• Location: Harbour Main-Bell Island
• Atlas of Canada Locator Map: Blackmarsh Gully
• GPS Coordinate Locator Map: Blackmarsh Gully Lat/Long