Canada (play /ˈkænədə/) is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west and northward into the Arctic Ocean. It is the world's second largest country by total area. Canada's common border with the United States to the south and northwest is the longest in the world. The land that is now Canada was inhabited for millennia by various groups of Aboriginal peoples. Beginning in the late 15th century, British and French expeditions explored, and later settled, along the Atlantic coast. France ceded nearly all of its colonies in North America in 1763 after the Seven Years' War. In 1867, with the union of three British North American colonies through Confederation, Canada was formed as a federal dominion of four provinces. This began an accretion of provinces and territories and a process of increasing autonomy from the United Kingdom. This widening autonomy was highlighted by the Statute of Westminster of 1931 and culminated in the Canada Act of 1982, which severed the vestiges of legal dependence on the British parliament.