High Quality Content by WIKIPEDIA articles! In the U.S. state of Colorado, U.S. Route 50 is a major highway crossing through the lower midsection of the state. It connects the Western Slope with the lower Front Range and the Arkansas Valley. The highway serves the areas of Pueblo and Grand Junction as well as many other smaller areas along its corridor. The long term project to upgrade the highway from two lanes to a four lane expressway between Grand Junction and Montrose was completed in January 2005. Only about 25% of the remainder of highway 50 in Colorado is four lane expressway.