The world’s longest border is shared by two of the world’s largest countries: Canada and the United States of America. Running 8,891 kilometres (5,525 miles) across the northern border of the United States and the southern border of Canada, this border is the longest continuous undefended national border in the world.
The border is marked by a variety of physical features, such as rivers, lakes, mountain ranges, and forests. The border also crosses several states in both countries, including Alaska, Idaho, Maine, Michigan, Minnesota, Montana, New York, North Dakota, Ohio, Pennsylvania, Vermont, and Washington in the US, and Alberta, British Columbia, Manitoba, New Brunswick, Newfoundland and Labrador, Northwest Territories, Nunavut, Ontario, Quebec, Saskatchewan, and Yukon in Canada.
The international boundary was first established in 1783 by the Treaty of Paris, which ended the Revolutionary War between Britain and the United States. Canada’s border with the United States was further clarified and established by the 1842 Webster-Ashburton Treaty, which resolved disputes between the two countries over their respective borders.
The border between the two countries is heavily regulated, with the two governments sharing responsibility for immigration, customs, and security. Both countries have a number of border crossing points, which are staffed by both Canadian and American border agents. Additionally, the two countries have collaborated on various joint initiatives, including the International Boundary Commission, which is responsible for maintaining the physical boundary markers and surveying the boundary line.
The Canada-US border is one of the most heavily traveled international borders in the world. Each year, millions of people cross the border for business, leisure, or to visit family and friends. The border is also an important economic corridor, with billions of dollars of trade crossing the border annually.
Despite the long and peaceful history between the two countries, the Canada-US border remains heavily regulated and monitored. The two governments continue to collaborate on various initiatives to ensure the safety and security of both countries, while also allowing for the efficient flow of people and goods across the border.