Hold on to your specs while peering down here. You'd have a long climb to the bottom if they fell off.  This rocky chasm in China is one of the world's deepest underground shafts. It stretches down for an astonishing 3,100ft, or 1,026 metres. An international team of cave explorers who discovered the cave, near the village of Tian Xing, are seen descending into the abyss.  The picture was taken by photographer Robert Shone, 28, of Manchester, who spent two months with the climbers documenting-their explorations. Camping underground for four to five days at a time, the team were able to explore the extensive network of caves and tunnels. Though unimaginably deep, the Chinese caves are actually dwarfed by others across the globe.  The world's deepest cave is Krubera in Georgia, which is 6,822ft deep, followed by Lamprechtsofen in Austria (5,354ft) and Gouffre Mirolda in France (5,335ft).  As an interesting comparison, the world's tallest peak, Mount Everest, is 29,029ft high.                 " DM