The Canadian Rockies are the easternmost part of the Canadian Cordillera, the collective name for the mountains of Western Canada. They form part of the American Cordillera, an essentially continuous sequence of mountain ranges that runs all the way from Alaska to the very tip of South America. The Cordillera in turn are the eastern part of the Pacific Ring of Fire that runs all the way around the Pacific Ocean.
The Canadian Rockies are bounded on the east by the Canadian Prairies, on the west by the Rocky Mountain Trench, and on the north by the Liard River. Contrary to popular misconception, the Rockies do not extend north into Yukon or Alaska, or west into central British Columbia. North of the Liard River, the Mackenzie Mountains, which are a distinct mountain range, form a portion of the border between the Yukon and the Northwest Territories. The mountain ranges to the west of the Rocky Mountain Trench in southern British Columbia are called the Columbia Mountains, and are not considered to be part of the Rockies by Canadian geologists.
The Canadian Rockies (French: Rocheuses canadiennes) comprise the Canadian segment of the North American Rocky Mountains. They are the eastern part of the Canadian Cordillera, which is a system of multiple ranges of mountains which runs from the Canadian Prairies to the Pacific Coast. The Canadian Rockies mountain system comprises the southeastern part of this system, lying between the Interior Plains of Alberta and Northeastern British Columbia on the east to the Rocky Mountain Trench of BC on the west. The southern end borders Idaho and Montana of the USA. In geographic terms the boundary is at the Canada/US border, but in geological terms it might be considered to be at Marias Pass in northern Montana. The northern end is at the Liard River in northern British Columbia.
The Canadian Rockies have numerous high peaks and ranges, such as Mount Robson (3,954 m (12,972 ft)) and Mount Columbia (3,747 m (12,293 ft)). The Canadian Rockies are composed of shale and limestone. Much of the range is protected by national and provincial parks, several of which collectively comprise a World Heritage Site.