The Rocky Mountains run from New Mexico northwest to the northern most part of British Columbia in Canada. Along the way, the mountain range cuts through Colorado, Wyoming, Montana and Idaho in the United States and the Canadian province of Alberta.
The Rocky Mountains distinction includes many other connected smaller mountain ranges that were created by tectonic activity at the same time, around 80 to 55 million years ago. All of the Rocky Mountains are located between the Rio Grande River in the south and the Liard River in Canada. Other mountain ranges that are considered to be a part of the Rocky Mountains include the Sangre de Cristo Mountains of New Mexico, the Absaroka-Beartooth range in Montana, and the Wind River Range and Big Horn Mountains of Wyoming.