At low tide, it’s sometimes hard to believe there’s water separating the island of Anglesey from Llanfairfechan. The eastern end of the Menai Strait (the water between Anglesey and the mainland) is much wider than the section west of Bangor. Here the tides cover and uncover an expanse of sand and mud of about 25 square km. The area extends some 9.5km west along the coastline from Llanfairfechan.
In medieval times the sands provided a key transport route between the mainland and Llanfaes, the main centre of religion and commerce in this corner of Anglesey before Beaumaris was developed. Passengers crossed the sands at low tide and took ferryboats over the remaining channel of water. In 1282 the forces of King Edward I installed wooden boats to create a pontoon across the channel for an invasion of Anglesey, but they were quickly repelled by men loyal to Prince Llywelyn.
Traeth Lafan and the adjoining coastal land form an important wildlife habitat. In autumn and winter the area hosts Britain’s largest group of moulting great crested grebes. Other birds seen here include oystercatchers, golden eye and red-breasted mergansers. Biodiversity here is enriched by the streams and rivers which flow across the sands, bringing freshwater from Snowdonia.