The Lleyn Peninsula is that long finger of land sticking out from north Wales. Right at the tip of the finger is Bardsey Island, known in Welsh as Ynys Enlli and regarded - for what reason I do not know - as holy. The pilgrim route to Bardsey ran along the north coast of the peninsula and churches and monasteries along the way offered hospitality to pilgrims.
One of these places is the little church at Pistyll, which nestles - there's no other word for it - in a hollow within sight of the sea. There's nothing terribly remarkable about the church itself, but the parishioners have adopted a charming - and as far as I know, unique - custom that makes the place well worth a visit.