The two countries that share the longest international border are Canada and the United States. This border stretches approximately 8,891 kilometers (5,525 miles), making it the longest international boundary in the world. The border encompasses a diverse landscape, including forests, mountains, lakes, and rivers. It is marked by numerous crossing points that facilitate trade and travel for millions of people each year. The Canada-U.S. border has a rich historical context, reflecting the shared interests and values of both nations. Its management includes various agreements and protocols to ensure security and efficient passage between the two countries.