In 1936, a portion of the McCullough Turnpike in Fayston, which was chartered in 1933 but proved unprofitable, was deeded back to the state of Vermont and renamed to McCullough State Highway. The road, which extended eastward from the Chittenden–Washington county line, was paved during the period of 1936 and 1940. The rest of the McCullough Turnpike to VT 100 in Waitsfield became part of the state highway system in 1956. In 1965, the state legislature authorized the extension of VT 17 from Bristol to the Addison–Chittenden county line, connecting it to the McCullough State Highway by way of Chittenden County's section of the former McCullough Turnpike. The VT 17 designation was extended eastward through Chittenden County and along the McCullough State Highway at this time.