- A478 between A477 and A4115, Pembrokeshire (Grid ref SN114100)
- A478 between A4218 Serpentine Rd and A477(T), Pembrokeshire (Grid ref SN114048)
- A478 between A4115 and A40(T), Pembrokeshire (Grid ref SN117149)
- A478 between A40 and Pembrokeshire boundary, Pembrokeshire (Grid ref SN118175)
- A478 between Pembrokeshire boundary and Pembrokeshire boundary, Pembrokeshire (Grid ref SN121203)
- A478 between Pembrokeshire boundary and Pembrokeshire boundary, Pembrokeshire (Grid ref SN121220)
- A478 between A40(T) and Pembrokeshire boundary, Pembrokeshire (Grid ref SN125228)
- A478 between A4139 White Lion St and A4218 Serpentine Rd, Pembrokeshire (Grid ref SN130010)
- A478 between Carmarthenshire boundary and Glandy Cross, Carmarthenshire (Grid ref SN133250)
- A478 between Carmarthenshire boundary and LA Boundry, Carmarthenshire (Grid ref SN152274)
- A478 between Glandy Cross and Carmarthenshire boundary, Carmarthenshire (Grid ref SN156276)
- A478 between Pembrokeshire boundary and B4332E, Pembrokeshire (Grid ref SN176300)
- A478 between Ceredigion boundary and A487, Ceredigion (Grid ref SN180443)
- A478 between B4332E and Pembrokeshire boundary, Pembrokeshire (Grid ref SN190401)