The A3017 number was allocated in 1935 to a link road between Hilsea and Portsmouth.
The road started on the A3 London Road just to the south of the Ports Bridge and headed southwest along Northern Parade, then south along Twyford Avenue. Although there is now a one-way system here, with southbound traffic deviating to use Stamshaw Road, this was actually the A3018 and the A3017 remained on Twyford Avenue throughout. The A3017 ended back on the A3 when that came in from the east along Kingston Crescent.
Although the A3017 was always a shorter route than the A3, it did not become the mainline of that road until the 1970s, following completion of the M275.