Old Monarch Pass (elevation 11,365 feet (3,464 m)) is a mountain pass on the border of Gunnison and Chaffee counties of west-central Colorado. It is located on the Continental Divide 0.6 miles (0.97 km) northwest of the current Monarch Pass where U.S. Route 50 crosses the divide. Old Monarch Pass divides the watersheds of Porphyry Creek, a tributary of Tomichi Creek and the Gunnison River, to the west and the South Arkansas River to the east. The name ‘‘Monarch’’ comes from nearby Monarch Ridge and the community of Monarch.