I also presume Signal Hill in our Tucson area was used for similar purposes.
I was just pointing out that the typical 50+ mile visibility we have here is better than that in North Wales....:^)
Yep. Growing up in Superior I was always interested in the ruins of old towns and roads in the area. Living in western Oregon now, I quite doubt such a comunication system would work given the fog and rain that we have daily. I’d imagine our weather is a lot like Wales. We miss the Arizona climate.