“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

Ngorongoro Crater (Tanzania). At 610m deep and 260 sq km, this is the largest unflooded caldera in the world. A blue-green vision from above it's a haven for engangered wildlife and Maasai livestock. The crater was formed three million years ago when a giant volcano, which could have been as high as Kilimanjaro, exploded and collapsed. The caldera formed the concentric fractures in the crust cracked down to a magma reservoir deep underground. (Photo by John Bryant/Getty Images)

Smoke billows from Jinnah International Airport in Karachi, Pakistan, June 9, 2014. (Photo by Athar Hussain/Reuters)

Vehicles clog a highway during a hazy day in Beijing, China, Wednesday, February 26, 2014. Beijing remained cloaked in hazardous white pollution hiding much of its skyline Wednesday, despite the announced closures or production cuts at 147 of the city's industrial plants. (Photo by Ng Han Guan/AP Photo)

Two rescued pangolins sit in a basket during a news conference in Bangkok on June 7, 2012. Thai customs rescued 110 pangolins worth about $35,500 that they say were to be sold outside the country as exotic food. The animals, hidden in a pickup truck, were seized at a customs checkpoint in Prachuap Khiri Khan province, south of Bangkok. (Photo by Sakchai Lalit/Associated Press)

A body of a victim lies trapped in the debris after an earthquake hit, in Kathmandu, Nepal April 25, 2015. Rescue efforts in Nepal are intensifying after nearly 2,000 people were killed on Saturday in the worst earthquake there in more than 80 years. Many countries and charities have offered aid to deal with the disaster. Seventeen people have been killed on Mount Everest by avalanches – the mountain's worst-ever disaster. Meanwhile a powerful aftershock was felt on Sunday in Nepal, India and Bangladesh, and more avalanches were reported near Everest. (Photo by Navesh Chitrakar/Reuters)

The rising sun illuminates the sky above the spires of a church in Vienna, Austria, November 17, 2015. (Photo by Heinz-Peter Bader/Reuters)

A conductor (C) collects fares from candy floss sellers as they travel in a tram to a marketplace early morning in Kolkata, India, December 23, 2015. (Photo by Rupak De Chowdhuri/Reuters)