O'Brian Lake is a Lake located in Nipissing, Ontario and has an elevation of 241 meters.

• Latitude: 46° 54' 5'' North   (decimal: 46.9013888)
• Longitude: 79° 21' 21'' West   (decimal: -79.3558333)
• Topography Feature Category: Lake
• Geographical Feature: Lake
• Canadian Province/Territory: Ontario
• Elevation: 241 meters
• Location: Nipissing
• Atlas of Canada Locator Map: O'Brian Lake
• GPS Coordinate Locator Map: O'Brian Lake Lat/Long