Explorers have just revealed a gigantic sinkhole hidden inside Phong Nha‑Ke Bang National Park. The story shows how satellite pictures, drones and a tough jungle trek can expose a secret forest and striking geology.

Kevin Ditamore, a member of the National Speleological Society, noticed an unusual dark area on Google Earth satellite imagery, prompting further investigation. His observation led the team to suspect a large underground feature.

After three drone surveys, the research team successfully pinpointed the sinkhole’s exact location. The aerial data gave them the coordinates needed to plan a ground expedition.

From July 23 to 29, 2025, a 24‑member expedition spent six days and five nights traveling more than 20 km through dense forest to reach the sinkhole. The team crossed sharp limestone ridges and dealt with limited water supplies during the trek.

The sinkhole’s opening measures about 190 m long and 140 m wide, widening to roughly 250 m by 200 m at the bottom, and it is about 120 m deep. Inside, a thriving primary forest grows, and expedition members used specialized climbing gear and safety rope systems to descend into the cavity and document its geological features.

The discovery demonstrates that modern remote‑sensing tools combined with determined fieldwork can uncover spectacular natural wonders that are invisible from the ground. It reminds us that many hidden landscapes may still await discovery.