The western freeway through the North Saskatchewan River valley and McKernan Ravine was the most controversial aspect of the plan, with public protests suspending construction shortly after clearing work had begun. In tandem with cost overruns, the project was cancelled in 1974. The cancellation of the METS freeway resulted in an alternate bypass route to be considered for Highway 16. At the time, 125 Avenue and Santa Rosa Road were collector roads which ran parallel to the Canadian National Railway; 125 Avenue was interrupted by the Edmonton Industrial Airport but the city had planned to connect the two segments to form an arterial roadway. In 1977, Alberta and Edmonton entered a cost-sharing agreement for the construction of Yellowhead Trail which included the expansion of 125 Avenue and Santa Rosa Road between 156 Street and 118 Avenue near the North Saskatchewan River, and a new extension westward to Highway 16X, which at the time entered Edmonton along 118 Avenue. Construction commenced in the late 1970s and was completed in 1984 with Yellowhead Trail as a 4-6 lane roadway. Interchanges opened at 118 Avenue / Victoria Trail in 1978, 97 Street and St. Albert Trail in 1982, and 170 Street in 1983. Following the completion of Yellowhead Trail, provincial highway designations were decommissioned within Edmonton's inner city; Highway 16 was designated to follow Yellowhead Trail east of 170 Street and Highway 2 followed Yellowhead Trail from St. Albert Trail to 170 Street before it continued south to Whitemud Drive and Calgary Trail.
