“Er Wang Dong (“Second Royal Cave”) is a large cave in the Wulong Karst region, in Wulong County of Chongqing Municipality of China. Current known length of its passages is 42,139 metres (138,251 ft) with a maximum depth of 441 m (1,447 ft). It is large enough to contain its own weather system. The cave starts in the 195 m (640 ft) deep Niubizi tiankeng (sinkhole) and also contains the 295 m (968 ft) deep Qingkou tiankeng. Er Wang Dong cave has formed in Lower Ordovician limestone and is located close to another very large cave system – San Wang Dong, which contains one of the largest cave chambers in the world – Cloud Ladder Hall. Both caves were explored by Hong Meigui Cave Exploration Society. Local people make weather forecast based on the observations in Niubizi tiankeng – if there is a fog coming from the cave, rain is expected”. – Wikipedia

“A team of expert cavers and photographers had been exploring caves in the Chongquing province of China – when they were amazed to discover the entrance to a hidden cave that was previously undiscovered. And they were stunned when they managed to enter the ginormous cave – and found that it was so large there was even a cloud inside it – a cave so large it has its own weather system. Photographer and caver Robbie Shone, from Manchester, was part of a team of 15 explorers on a month-long expedition who stumbled across the natural wonder”. – Caters News

American speleologist Erin Lynch leads Lars Abromeit down a steeply descending path into a deep gorge on the way to Er Long Dong and Cloud Ladder Hall. (Photo by Robbie Shone/Caters News/ImagineChina)

Gaining height step by step Hong Meigui member; Duncan Collis climbs a thin rope up to a small ledge overlooking the vast floor surface of Niubizi Tian Keng in the Er Wang Dong cave system. (Photo by Robbie Shone/Caters News/ImagineChina)

Climbing the rope up a vertical section of cave known as a pit in Xinu Attic. (Photo by Robbie Shone/Caters News/ImagineChina)

Hong Meigui co-founder Erin Lynch negotiates a re-belay before descending down into the black chasm below her. A deafening waterfall plummets behind, whipping up wind and spray into the air. This is the entrance to a section of cave called Queen of the Nile underground in San Wang Dong. (Photo by Robbie Shone/Caters News/ImagineChina)

Suspended on a thin rope, engulfed in cloud and lost in time, a tiny figure is dwarfed by the sheer size on a monumental scale of Cloud Ladder Hall. The beam of light cast by anothers head torch pierces the fog yet illuminates nothing. This naturally formed room is so large it has its own weather system going. (Photo by Robbie Shone/Caters News/ImagineChina)

Large stalagmites at the foot of a giant ascending ramp to another level of development in San Wang Dong create a spectacle mid way through a section of cave called Crusty Duvets. (Photo by Robbie Shone/Caters News/ImagineChina)

Erin Lynch and Lars Abromeit as they try to remain dry through the awkward sections of Queen of the Nile, deep underground in San Wang Dong. (Photo by Robbie Shone/Caters News/ImagineChina)

Erin Lynch drills another hole to contiue her traverse above the white water and descending waterfall into the blackness beyond. (Photo by Robbie Shone/Caters News/ImagineChina)

Calmer waters crystal clear pools and slow moving streams make it easier to explore Quankou Dongs main river passage. (Photo by Robbie Shone/Caters News/ImagineChina)

Blind Fish without any eyes swim around in small pools of water in Qi Dong. (Photo by Robbie Shone/Caters News/ImagineChina)

Perfectly situated in the middle of the passage this giant calcite stal boss makes a huge statement. Dwarfed by it's sheer size, Hong Meigui team member; Matt Ryan can only look up in amazement. This is one of many gigantic formations in San Wang Dong. (Photo by Robbie Shone/Caters News/ImagineChina)

Gravely battling the elements; American speleologist Erin Lynch struggles to pull her way across a raging torrent of white water that relentlessly bombards her with waves and waves of crashing water, wanting to tear her away from her only lifeline and throw her down the main river in Quankou Dong. (Photo by Robbie Shone/Caters News/ImagineChina)

Hong Meigui team members; Duncan Collis and Matt Ryan make progress along an awkward stretch of passage known as; Where the Wind Blows underground in San Wang Dong, suitably named because of the strong wind that whistles through this small restriction churning up dust and sand particles into the air. (Photo by Robbie Shone/Caters News/ImagineChina)

Two cave explorers are dwarfed for scale in a section of cave called Dancing Elephant Troop. Here two huge passages intercept and form a giant section of empty space, deep underground in San Wang Dong. (Photo by Robbie Shone/Caters News/ImagineChina)

The underground camp in Sang Wang Dong is a cosy and warm place to stay. Hot food and drink recharge weary and tired explorers before taking a few hours sleep in either suspended hammocks or on roll mats on the floor. (Photo by Robbie Shone/Caters News/ImagineChina)

The view back towards the towering entrance and the main river passage in Quankou Dong. Thick beds of limestone break through towards the ceiling high up above the floor of the cave. (Photo by Robbie Shone/Caters News/ImagineChina)