Explanation:

    Canada, which is just to the north of the United States, or immediately north of the  United States, shares a border (or separating line) with 13 U.S. states. The border is 5,522 miles (or 8,891 kilometers) long, which makes it the longest border between two countries in the world. It includes the long border on the southern end of Canada and also the border between Canada and the state of Alaska, in northwestern Canada.

    The U.S.-Canadian border is non-militarized, meaning that the U.S. and Canadian armies are not usually on the border. The border is also not normally patrolled, so people from the government are not usually watching the border to look for problems. However, there are 140 customs stations on the border, which are places where a government official (or a person who works for the government) asks people why they are entering the country and what they are bringing with them to make sure that they aren’t buying things in one country and selling them in the other country. Every year, the U.S.-Canadian border is crossed more than 100 million times.

    The U.S.-Canadian border has changed many times. The first border between the two countries was demarcated (or drawn on a map) in 1783. The last time the border was changed was in 1903. Today there are no border disputes or disagreements about where one country ends and the other country begins.

 

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