The longest mountain range in the United States is the Rocky Mountains. The Rockies, as they are commonly called, also stretch across Canada and Mexico.
The Rocky Mountains stretch over 3,000 miles in total and lie in Wyoming, Colorado, Idaho, Montana and the northern part of New Mexico. With an elevation of 14,400 feet, Mount Elbert in Colorado is the highest peak in the Rocky Mountain range. There are more than 1,000 types of flowering plants and trees in the Rocky Mountain ecosystem. The Rockies are a popular tourist destination for outdoor thrill seekers who enjoy mountain climbing, camping, skiing and fishing.