Aerial Photo taken on April 19, 2020 shows the scenery of Dashiwei Tiankeng, a giant karst sinkhole, at Leye-Fengshan Global Geopark in south China's Guangxi Zhuang Autonomous Region. The Leye-Fengshan Geopark was added to the UNESCO's Global Geopark List in 2010. The geopark contains large subterranean rivers, natural bridges and extensive cave systems. (Xinhua/Zhou Hua)

Aerial Photo taken on April 19, 2020 shows a Tiankeng, or giant karst sinkhole, at Leye-Fengshan Global Geopark, south China's Guangxi Zhuang Autonomous Region. The Leye-Fengshan Geopark was added to the UNESCO's Global Geopark List in 2010. The geopark contains large subterranean rivers, natural bridges and extensive cave systems. (Xinhua/Cao Yiming)

Aerial Photo taken on April 19, 2020 shows a Tiankeng, or giant karst sinkhole, at Leye-Fengshan Global Geopark, south China's Guangxi Zhuang Autonomous Region. The Leye-Fengshan Geopark was added to the UNESCO's Global Geopark List in 2010. The geopark contains large subterranean rivers, natural bridges and extensive cave systems. (Xinhua/Cao Yiming)

Aerial Photo taken on April 19, 2020 shows the scenery of Leye-Fengshan Global Geopark, south China's Guangxi Zhuang Autonomous Region. The Leye-Fengshan Geopark was added to the UNESCO's Global Geopark List in 2010. The geopark contains large subterranean rivers, natural bridges and extensive cave systems. (Xinhua/Zhou Hua)

Aerial Photo taken on April 19, 2020 shows the scenery of Dashiwei Tiankeng, a giant karst sinkhole, at Leye-Fengshan Global Geopark, south China's Guangxi Zhuang Autonomous Region. The Leye-Fengshan Geopark was added to the UNESCO's Global Geopark List in 2010. The geopark contains large subterranean rivers, natural bridges and extensive cave systems. (Xinhua/Zhou Hua)

Aerial Photo taken on April 19, 2020 shows a Tiankeng, or giant karst sinkhole, at Leye-Fengshan Global Geopark, south China's Guangxi Zhuang Autonomous Region. The Leye-Fengshan Geopark was added to the UNESCO's Global Geopark List in 2010. The geopark contains large subterranean rivers, natural bridges and extensive cave systems. (Xinhua/Zhou Hua)