"Northern Borders" is a term that often refers to the geographical and political boundaries located in the northern regions of a country. These borders can include land, rivers, and other natural features that define the limits of a nation. They play a crucial role in international relations, trade, and security. In the context of the United States, the Northern Border specifically refers to the boundary between the U.S. and Canada. This border is the longest international land border in the world, stretching over 5,525 miles. It is significant for trade, travel, and cultural exchange between the two countries.