It's there to show that your crossing into a different country's territory.
8891 kms
Canada
the equator...... i think
Niagara Falls?
The Niagara Falls.
the country that forms the northern boundary of the United States is Canada :)
The 49th Parallel
What saint Lawrence river forms a boundary between the Canadian province of
The Monroe Doctrine
Niagra Falls
The closest boundary to the U.S. is the maritime boundary with Canada, specifically in the Bering Sea. This boundary is located near the Aleutian Islands, where the U.S. and Canada have defined their respective territorial waters. Additionally, the U.S. shares a land border with Canada, which is the longest international land border in the world.
US and Canada