what country lies to the south of canada
United States
Canada
 Its southern and western border with the United States, stretching , is the world's longest bi-national land border. 
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Canada [SEP] Introduction
Canada is a country in the northern part of North America. Its ten provinces and three territories extend from the Atlantic to the Pacific and northward into the Arctic Ocean, covering , making it the world's second-largest country by total area. Its southern and western border with the United States, stretching , is the world's longest bi-national land border. Canada's capital is Ottawa, and its three largest metropolitan areas are Toronto, Montreal, and Vancouver. Various indigenous peoples inhabited what is now Canada for thousands of years before European colonization. Beginning in the 16th century, British and French expeditions explored and later settled along the Atlantic coast.