Dublin's Hellfire Club has been a place shrouded in myth and mystery; its infamy stems from the fact it was built using stone from ancient tombs - essentially grave robbing. Archaeologists who began digging up the grounds last month have stumbled across rock art believed to be 5,000 years old.
     The stone carving is so faint it is almost imperceptible to the naked eye; the team admit they almost missed it. Neil Jackman, who is leading the archaeological project, said: "The low autumnal sun hit the stone at an angle that revealed a previously unnoticed long curving line. As we looked at the line, the changing light revealed that the line cut over the top of two faint concentric circles, one inside the other. This is a motif that appears in megalithic art at some of the most famous passage tombs in the country."
     The team immediately sent images of the carvings to megalithic art experts at University College Dublin (UCD) for examination.
     Unfortunately, the archaeologists were not the first visitors to the site to miss the stone's significance. The beauty spot is set high in the Dublin mountains and has been the scene of many a barbeque, bonfire and hellfire over the years. The carved stone itself had been badly damaged by flames and Mr Jackman said that "due to the many fires that had been lit upon it, it fractured into four large fragments as we began to lift it from the trench".
     Broken or not, the archaeologists still view the stone as highly significant and have given it to the National Museum of Ireland for further analysis.

Edited from BBC News (4 November 2016)