Son Doong, Vietnam 🇻🇳

Cave in Vietnam, the largest cave in the world.

Located in Central Vietnam, in Quang Binh province, in Phong Nha-Ke Bang National Park, 500 kilometers south of Hanoi and 40 km from the provincial center - Dong Hoi.

The cave has an underground river that floods some parts of the cave during the rainy season.
The total volume of the cave is estimated at 38.5 million m³.