Answer:
It's an international border...
Step-by-step explanation:
The border was an established agreement between the U.S. and Britain
The treaty between the U.S. and Britain, established the 49th parallel from the Rocky Mountains to the Strait of Georgia; this is the boundary between the U.S. and Canada.
This agreement took place in 1818.
tbh I'm kinda confused by what you're asking
I hope what I put answers your question tho