| Name | Locality | Local Authority | Administrative area |
| Bwgan-ddu Lane | Marchwiel | Wrecsam / Wrexham | Wrecsam / Wrexham |
| Bwl Road | Nelson | Caerffili / Caerphilly | Caerffili / Caerphilly |
| Bwlch Alltran | Holyhead | Sir Ynys Mon / Isle of Anglesey | Sir Ynys Mon / Isle of Anglesey |
| Bwlch Carnygelli | Gelligaer | Caerffili / Caerphilly | Caerffili / Caerphilly |
| Bwlch Carnygelli | Aber Valley | Caerffili / Caerphilly | Caerffili / Caerphilly |
| Bwlch Carnygelli | Nelson | Caerffili / Caerphilly | Caerffili / Caerphilly |
| Bwlch Crescent | Neath | Castell-nedd Port Talbot / Neath Port Talbot | Castell-nedd Port Talbot / Neath Port Talbot |
| Bwlch Farm Road | Conwy | Conwy / Conwy | Conwy / Conwy |
| Bwlch Gwynt | Pistyll | Gwynedd / Gwynedd | Gwynedd / Gwynedd |
| Bwlch Lane | Abergwili | Sir Gaerfyrddin / Carmarthenshire | Sir Gaerfyrddin / Carmarthenshire |
| Bwlch Oernant | Llantysilio | Sir Ddinbych / Denbighshire | Sir Ddinbych / Denbighshire |
| Bwlch Oernant | Llandegla | Sir Ddinbych / Denbighshire | Sir Ddinbych / Denbighshire |
| Bwlch Penbarras | Llanbedr Dyffryn Clwyd | Sir Ddinbych / Denbighshire | Sir Ddinbych / Denbighshire |
| Bwlch Penbarras | Llanferres | Sir Ddinbych / Denbighshire | Sir Ddinbych / Denbighshire |
| Bwlch Road | Neath | Castell-nedd Port Talbot / Neath Port Talbot | Castell-nedd Port Talbot / Neath Port Talbot |
| Bwlch Road | Llwchwr | Abertawe / Swansea | Abertawe / Swansea |
| Bwlch Road | Baglan | Castell-nedd Port Talbot / Neath Port Talbot | Castell-nedd Port Talbot / Neath Port Talbot |
| Bwlch Road | Cwmavon | Castell-nedd Port Talbot / Neath Port Talbot | Castell-nedd Port Talbot / Neath Port Talbot |
| Bwlch Road | Fairwater | Caerdydd / Cardiff | Caerdydd / Cardiff |
| Bwlch Y Ddeufryn | Gwernaffield | Sir y Fflint / Flintshire | Sir Y Fflint / Flintshire |
| Bwlch Y Ffordd | Ganllwyd | Gwynedd / Gwynedd | Gwynedd / Gwynedd |
| Bwlch Y Gwyn | Mawr | Abertawe / Swansea | Abertawe / Swansea |
| Bwlch Y Maen | Betws-y-Coed | Conwy / Conwy | Conwy / Conwy |
| Bwlch-y-clawdd Road | Ogmore Valley | Pen-y-bont ar Ogwr / Bridgend | Pen-y-bont Ar Ogwr / Bridgend |
| Bwlch-y-clawdd Road | Treorchy | Rhondda Cynon Taf / Rhondda Cynon Taf | Rhondda Cynon Taf / Rhondda Cynon Taf |
| Bwlch-y-gwynt Road | Llysfaen | Conwy / Conwy | Conwy / Conwy |
| Bwlchygwynt | Llanelli | Sir Gaerfyrddin / Carmarthenshire | Sir Gaerfyrddin / Carmarthenshire |
| Bwllfa Road | Aberdare | Rhondda Cynon Taf / Rhondda Cynon Taf | Rhondda Cynon Taf / Rhondda Cynon Taf |
| Bwllfa Road | Morriston | Abertawe / Swansea | Abertawe / Swansea |
| Bwrw Road | Llwchwr | Abertawe / Swansea | Abertawe / Swansea |
| Bwthyn Y Mynach | Bangor | Gwynedd / Gwynedd | Gwynedd / Gwynedd |
