Motorway gantry sign
A gantry spanning the motorway with blue overhead signs showing the following text.
Forward destinations: Caerdydd (G a Gn); Cardiff (N & W) Pen-y-bont; Bridgend M4 .
Exit destinations: Caerdydd (Dn a D); Cardiff (E & S) A48(M) .
Junction number: 29.
The A48(M) is a little motorway spur leading on to Cardiff's main approach, the A48 Eastern Avenue.