ナショナルジオグラフィックのインスタグラム(natgeo) - 5月10日 01時16分

Photo by @shonephoto (Robbie Shone) - In January 2016, an international caving expedition travelled to the island of New Britain in Papua New Guinea. The goal? To find and explore this area's last remaining unexplored mega-doline, called The Black Hole, which was identified from aerial observations.

With renewed vigour the team eagerly went in search of caves and discovered this one (pictured) named Gouffre Christian Rigaldie, which at 700m (2200ft) deep was the largest and deepest cave the team discovered on this 2016 expedition. It was found really close to base camp, within less than an hours hike. Interestingly, the beautiful formations in this cave were made of gypsum, making it quite unique amongst the more common calcite formations. More from this story on my personal feed - @shonephoto

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