Porth Penial Dowyn is a long beach of mostly coarse sand and light shingle backed by agricultural land. It is reached either along a single track lane from the village of Llanfwrog, or by a good public footpath from Llanfachraeth. There are some places to park at the very end of the lane on the back of the beach or nearby, but care needs to be taken not to obstruct farm access. Parking is easier to find at either of the two villages if you don't mind a walk. The beach is opposite Holyhead harbour, and signs warn of large waves generated by ferry movements.The photos were taken an hour after high tide.