Only in 2009 did the cave become internationally known after a group of scientists from the British Cave Research Association, led by Howard and Deb Limbert, conducted a survey in Phong Nha-Kẻ Bàng from 10 to 14 April 2009.Their progress was stopped by a large, 60-metre (200 ft) high calcite wall, which was named The Great Wall of Vietnam. It was traversed in 2010 when the group reached the end of the cave passage.