The A4080 is a British A road which is located on the Island of Anglesey, Wales. It follows a very roundabout route from the A5 road at Llanfairpwllgwyngyll via Newborough and Rhosneigr back to the A55 and the A5 about 9 miles (14 km) south of Holyhead. In all the road is about 17 miles (27 km) long.