Big Boundary Island is a Island located in Frontenac, Ontario and has an elevation of 254 meters.

• Latitude: 44° 48' 40'' North   (decimal: 44.8111111)
• Longitude: 76° 59' 22'' West   (decimal: -76.9894444)
• Topography Feature Category: Island
• Geographical Feature: Island
• Canadian Province/Territory: Ontario
• Elevation: 254 meters
• Location: Frontenac
• Atlas of Canada Locator Map: Big Boundary Island
• GPS Coordinate Locator Map: Big Boundary Island Lat/Long