The Rockies are a younger mountain range formed by different geological processes, resulting in steeper slopes and higher peaks compared to the older, more eroded Appalachians.

The Rocky and Appalachian mountain ranges differ significantly in age and formation. The Appalachians are much older, formed hundreds of millions of years ago and subsequently eroded over time, resulting in rounded peaks and gentler slopes. The Rockies, formed more recently during the Laramide Orogeny, are younger and have undergone less erosion, resulting in steeper slopes, higher peaks, and more rugged terrain.