Penlan?
After reading about the Penlan Ponds project for Powys I can see where SDQ has had his answer from and he's the nearest so half a point to SDQ.
The answer is actually Granllyn but it's
because I have no more clues for this one.
I had a look at the property years ago with a view to buying it. It had potential and a red corrugated roof covered the thatch but the planning office would only let me extend it by 50 per cent and not the 100 per cent I needed. That and the fact that it two septic tanks in the garden from the cottages across the road put me off buying it.