The A4042 is a trunk road that runs from Abergavenny to Newport in the United Kingdom.

It begins on junction of the A40 and A465 south of Abergavenny and then travels southwards towards Little Mill north of Pontypool. This section is a single carriageway and is notoriously winding and undulating. From Little Mill onwards the road becomes a dual carriageway, passing Pontypool and Cwmbran before crossing the city boundary into Newport. Here the road has a junction (25A) with the M4 motorway and south from there loses its primary status and becomes an urban road. The first section of which, called Heidenheim Drive,[1] is an elevated roadway through the Crindau district. It then becomes a surface street called Kingsway that passes through the city centre, and continues on as Usk Way until its junction with the A48 Southern Distributor Road in the south of the city.


Northbound exits Junction Southbound exits
Merthyr Tydfil, Hereford A465
Abergavenny, Brecon, Monmouth A40
Ysbytty Fields Roundabout Start of A4042
Llanfoist B4269 Llanellen Junction Llanfoist B4269
Usk A472 Little Mill Junction Usk, Little Mill A472
Mamhilad Mamhilad Roundabout Mamhilad
New Inn New Inn Roundabout New Inn
Pontypool A472 (A4043) Pontymoile Roundabout Pontypool A472 (A4043)
Cwmbran A4051
New Inn
Craig-y- Felin New Inn
Cwmbran A4051
Croesyceiliog Croesyceiliog Roundabout Croesyceiliog
Caerleon B4236
Turnpike Roundabout Caerleon B4236
Crown Roundabout Llantarnam
Cwmbran A4051 Croes-y-Mwyalch Cardiff A4051 (M4 (W))
Start of A4042 Grove Park London, Chepstow A4042 (M4 (E))
Northbound exits Junction / Interchange Southbound exits
London, Chepstow A4042 (M4 (E))
Caerleon B4596
Grove Park Start of A4042
Cardiff A4051 (M4 (W)) Harlequin Cardiff A4051 (M4 (W))
City Centre
Civic Centre B4591
Exit only
Old Green Interchange Access only
Cattle market
Old Town Docks
Octopus Bridge Old Town Docks
Start of A4042 Old Town Dock (M4 (E)), Pilgwenlly, Docks, (M4 (W)) A48
1.000 mi = 1.609 km; 1.000 km = 0.621 mi

See also


  1. ^ Named after one of Newport's twin towns.

External links

Coordinates: 51°43′05″N 2°59′29″W / 51.71809°N 2.99137°W / 51.71809; -2.99137