Longest boundary
- Who
- Unknown
- When
- 01 January 0001
The longest boundary in the world is that between Canada and the United States, which (including the Great Lakes boundaries) extends for 6,416 km (3,986 miles) (excluding the frontier of 2,547 km (1,582 miles) with Alaska). If the Alaskan boundary is added the US-Canada boundary is 8,963 km (5,569 miles) long.
If the Great Lakes boundary is excluded, the longest land boundary is that between Chile and Argentina, which is 5255 km (3265 miles) in length.
If the Great Lakes boundary is excluded, the longest land boundary is that between Chile and Argentina, which is 5255 km (3265 miles) in length.