ナショナルジオグラフィックのインスタグラム(natgeo) - 5月6日 14時32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.
Following the team’s disappointment at discovering The Black Hole was only a blind pit with no way through to the river cave beneath, they turned their attention to other features they had noted from the aerial photographs, maps, and walking the trail to The Black Hole. They began with following a surface stream in a deep channel through the rainforest, which suddenly plunged underground and into a giant vertical pit, approximately 5m wide x 80m (15ft x 250ft) deep. This led into a beautifully decorated, horizontal gallery (pictured) that was full of white calcite and stalactites covering the ceiling and walls. Unfortunately there was no way beyond this beautiful chamber and no way down and into the main river cave below.
More from this story on my personal feed - @shonephoto

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