The Rocky Mountains, also known as the Rockies, are a major mountain range and the largest mountain system in North America. The Rocky Mountains stretch 3,000 mi (4,800 km) in straight-line distance from the northernmost part of western Canada, to New Mexico in the southwestern United States. Depending on differing definitions between Canada and the United States, its northern terminus is located either in northern British Columbia's Terminal Range south of the Liard River and east of the Trench, or in the northeastern foothills of the Brooks Range/British Mountains that face the Beaufort Sea coasts between the Canning River and the Firth River across the Alaska-Yukon border. Its southernmost point is near the Albuquerque area adjacent to the Rio Grande rift and north of the Sandia–Manzano