Porth y Nant is a very sheltered and secluded cove, about 60 yards wide, consisting mostly of rocks and shingle with a little sand. In one corner a small stream cascades down the near vertical cliffs. Access is a short and fairly easy climb / scramble down the rocks on the south side. This is one beach you'll probably have all to yourself, apart from a few oystercatchers and rock pipits.
Neighbouring it on the south side is Porth y Bribys. This is a narrow cove of shingle, rocks, rockpools and a small cave. It can be reached by scrambling with great care down a very steep bank and scree slope at the back of the beach. However, there are some burrows here that indicate the presence of nesting birds, so this one is probably best left to nature.
The nearest parking is as for Fydlyn, at Grid Ref: SH303914. The photos were taken at mid-tide.