Between 1964 and 1972, a completely new route from Calgary to Canmore was built. The route included new overpasses, bridges, the Canmore Bypass, and 4 lane divided highway. In 1976, Parks Canada began twinning Highway 1 through Banff National Park, with the highway twinned to Banff by 1985 and to Castle Junction by 1997. Twinning of the section between Castle Junction and the British Columbia border was completed in 2014, with the final of Highway 1 between Lake Louise and the British Columbia border opening to traffic on June 12 of that year. Between 1973 and 1990 the highway was twinned from Calgary to the Saskatchewan Border.