Coal Bank Pass is a high mountain pass at an elevation of 3.243m (10,640ft) above the sea level, located in the San Juan Mountains of western Colorado in the United States. The pass is traversed by the Million Dollar Highway.
The road over the pass, officially called U.S. Highway 550, is asphalted. It is usually open all year, but it can be closed anytime when the access is not cleared of snow. Summer temperatures can range from 70–90 °F highs at the ends of the highway to 50–70 °F in the mountain passes. The snow season starts in October, and snow will often close the road in winter. Chains may be required to drive. The grades on the south face of this climb are much more reasonable than the north face.
The weather on this zone is harsh and highly unpredictable and it does not take much time for the bright sun shine to change over to moderate to heavy snow fall. While the north side is fairly gentle, the descent on the south side is pretty steep (6.5%), and has a runaway truck ramp for trucks that lose control. The scenery of the San Juan’s is unsurpassed and many call this area the American Alps.