O'Brien Lake is a Lake located in Renfrew, Ontario and has an elevation of 354 meters.

• Latitude: 45° 21' 58'' North   (decimal: 45.3661111)
• Longitude: 77° 6' 25'' West   (decimal: -77.1069444)
• Topography Feature Category: Lake
• Geographical Feature: Lake
• Canadian Province/Territory: Ontario
• Elevation: 354 meters
• Location: Renfrew
• Atlas of Canada Locator Map: O'Brien Lake
• GPS Coordinate Locator Map: O'Brien Lake Lat/Long