A massive lightning strike which hit the Isle of Lewis more than 3,000 years ago may have inspired ancient civilisations to build stone circles, academics believe. Scientists studying a prehistoric stone circle on the Outer Hebrides island discovered evidence of a lightning strike on a nearby site where a circle had been hidden beneath a peat bog. Just one stone remained standing at the site, known as Site XI or Airigh na Beinne Bige, which overlooks the main stone circle, Tursachan Chalanais, at Calanais on the Isle of Lewis. But it is believed that the single stone was once part...