Canada is a country in North America. Its ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's second-largest country by total area, with the world's longest coastline. Its border with the United States is the world's longest international land border. The country is characterized by a wide range of both meteorologic and geological regions. With a population of just over 41 million people, it has widely varying population densities, with the majority residing in urban areas and large areas of the country being sparsely populated. Canada's capital is Ottawa and its three largest metropolitan areas are Toronto, Montreal, and Vancouver.