I live near Dinorwig pumped storage hydro and can highly recommend the tours they do if you're in the area. The tour bus drives into the mountain and stops lite

I live near Dinorwig pumped storage hydro and can highly recommend the tours they do if you're in the area. The tour bus drives into the mountain and stops literally a few metres from the generating turbines where you can get out and take photos of the huge underground turbine hall.