This article is about the original route from Yarnbrook to Chippenham.
For the reserved route in north Devon, replaced by the A361, see A364 (Barnstaple - Bamford)
The now-unclassified former A364 through Lacock
The A364's original, 1922, route was from Yarnbrook, just south of Trowbridge on the then-A363, north via Melksham to Chippenham.
However, in 1935, it was then decided to extend the A350 number past its original terminus in Warminster, along the A363 as far as Yarnbrook and along the entire length of the A364, creating a coherent south/north route from the south coast to the A4. (It has subsequently been extended along the former A429 to meet the M4.) The ex-A364 remains this number, although sizeable sections of the road have since been bypassed.