EXTRAORDINARY photographic evidence has been uncovered of a second blasting tunnel dug into the heart of Nobbys headland during the 1850s.The glass lantern slide, taken by a government geologist at the turn of last century, was recently identified by Coal River Working Party geologists Roslyn Kerr and Russell Rigby.It is the only known image of the tunnel's entrance, which today is covered by rubble and bitou bush.Historical records reveal the tunnel, and another situated about 50 metres to the east, were bored with the intention of blowing up the headland.The plan was ultimately scuttled due to a massive public outcry - the city's first environmental protest."We think the tunnels are at least 24 metres each, and probably did not meet in the middle of the headland," Ms Kerr said. Coal River Working Party chairman Gionni DiGravio said the discovered photo confirmed historical and anecdotal accounts of the second tunnel's existence.They include an account by former Newcastle East resident Maurie Lynch who told researcher Noel Davies 1994 that he played in the tunnel as a boy.Ms Kerr said the Coal River Working Party hoped to obtain permission to do a preliminary inspection of the tunnel's entrance in preparation for further archaeological works.