The Rocky Mountains were formed primarily through the process of plate tectonics.

Specifically, the collision and convergence of tectonic plates, particularly the North American Plate and the Pacific Plate, caused the Earth's crust to buckle and uplift, leading to the formation of this majestic mountain range. This tectonic activity created various geological features, including peaks, valleys, and ridges that define the Rockies today. While erosion and glaciation have shaped the mountains over time, the initial formation is attributed to these powerful tectonic forces, making it a prime example of mountain-building processes in Earth’s history.