The A4219 is a short link road in north Pembrokeshire allowing traffic to pass between the A40 and A487 to the south of Fishguard. The road was unclassified for many years but seems to have gained its number in the 1960s.
The road starts on the A40 to the north of Scleddau. Initially it heads southwest but soon bends sharply right to run northwestwards and is soon heading due north. It descends gently for much of its route, passing a few buildings but reaching no places of any size. The road soon skirts the edge of a wood and bends sharply left to cross a narrow bridge over the Fishguard branch line. The road ends soon afterwards at a T-junction on the A487.