Never heard of the song before. But I have been to the Glen of Aherlow. It is one of the most beautiful places I have ever been to. We were fishing in a crystal clear stream for trout the like that I had never seen before! They were swimming around our feet as we waded upstream, bright metallic rainbow hues. The scenery surrounding us was like a dream. This was in 1980. I hear that the stream was later polluted by sillage and thousands of fish died. What is it like there nowadays?