The only country that shares a border with Canada is the United States. From coast to coast, southern Canada is bordered by the northern are of the continental United States, and the northwest tip of Canada is bordered by the American state of Alaska.
At 5,525 miles long, the Canada-United States border is the longest land border in the world. Although there are officially staffed border crossings, the two countries are peaceful neighbors, and the border is essentially undefended. The rest of Canada is bordered by the Pacific, Atlantic and Arctic Oceans, and its 151,485 mile-long coastline is the longest in the world.