While the major mountain-building events are long past, the Rockies are still experiencing very slow uplift due to ongoing tectonic activity.

The primary formation of the Rocky Mountains occurred millions of years ago. Although the intense mountain-building events have ceased, the Rockies are still subject to minor tectonic activity. This results in very slow rates of uplift, measured in millimeters per year. While erosion is also constantly wearing down the mountains, the slow uplift means they are technically still growing, albeit at a nearly imperceptible pace.