On a topographical map of western North America, you can see a long, mountainous backbone stretching all the way from Alaska to Mexico. This backbone is part of the American Cordillera – a series of overlapping and parallel mountain ranges that include the Brooks Range in Alaska, the Rocky Mountains straddling Canada and the US, and the Western Sierra Madre in Mexico.

The Yellowstone to Yukon region is part of the American Cordillera, which is comprised of three main mountain ranges: the Rocky Mountains, Columbia Mountains, and Mackenzie Mountains. All three of these ranges are unique geologically, politically, socially, and economically – and they essentially represent the last intact mountain ecosystem in the entire American Cordillera, outside of Alaska.

Rocky Mountains

Photo: Dave Simons

Spanning all the way from the northern most part of British Columbia into New Mexico, the Rocky Mountains form a significant portion of North America's western Continental Divide. The Rockies are comprised of several different ranges, including the Continental, Clark, Wind River, and Rocky Mountain Front Ranges. The Rockies contain some of North America's most iconic national parks, including Banff, Jasper, Glacier, Yellowstone, and the Grand Tetons, and continue to draw people from around the world.

Columbia Mountains

The Columbia Mountains are located primarily in British Columbia, but also extend south into portions of Montana, Idaho, and Washington. These mountains lie west of the Rockies across the Rocky Mountain Trench, a long, trench-like geographic feature created by rock fracturing over geologic time. The Columbia Mountains include the Purcell, Selkirk, Cariboo, and Monashee Ranges, which are some of the most important ranges within the Y2Y region for wide-ranging wildlife. The Purcells and Selkirks are home to a critically endangered mountain caribou herd, as well as several small grizzly bear populations that straddle the US-Canada border.

Mackenzie Mountains

Named after Alexander Mackenzie, Canada's Prime Minister from 1873 to 1878, the Mackenzie Mountains form part of the boundary between the Yukon and Northwest Territories. The Peel River is at the north end of these mountains, with the Liard River at the sound end. Nahanni National Park Reserve, one of the largest and most important protected areas for wildlife in the northern Y2Y region, lies within this mountain system. The Mackenzie Mountains also contain Tombstone Territorial park, which helps protect the porcupine caribou herd. Only two roads lead into the mountains, both from the Yukon side. One of the roads leads to the town of Tungsten, which holds about 55 percent of the world's known reserves of that metal.