Pwlldu Quarry

This was the source of the export trade - limestone. The local farmers used lime as a fertiliser on their fields and agriculture became very profitable but as their land was resting on limestone they could produce their own. Look across the Bristol channel from Pwlldu and you are seeing Somerset and Devon where the soil is acidic and heavy in clay. Lime neutralises acidity and breaks up a heavy clay soil so a thriving trade was established across the sea. The boats used were made of wood and if they were to have carried the lime itself that lime would have eaten into the wood so the export would have been the limestone itself. That answers the question "Why are there so many old lime kilns in some coastal areas?"