The cave of Hang Sơn Đoòng is the biggest in the world and it is located in Vietnam, inside the Phong Nha-Ke National Park in the region of Quang Binh. The length of the cavity exceeds 5 km (3 miles) and its principal passage is the biggest and majestic in the world, with a volume of 38.4×106 cubic meters ( 1355 × 354 cubic feet). One of its peculiarities is the one linked to the dolines, which let the light filter through the upper walls. This has made possible an inside vegetation such as trees and big plants.
Some of the highest stalagmites in the world can be found in this cave with a maximum length of 70 metri (230 ft)
A Random and Incredible Discovery
In the ’90s, a farmer named Hồ Khanh was illegally working as a logger at Bố Trạch. In 1991, during a jungle expedition to extract agar wood, the man discovered the huge cave access with a great river running through it. Khanh didn’t take the risk to go inside without any ropes or climbing gear. He left his work as a logger and came back to his family to live as local farmer, but he never forgot the extraordinary cave that he randomly came across.
An Unique Climate
Sơn Đoòng is not unique only because of its hugeness, but also since it has its very own climate inside. The multitude of collapses happened throughout millions of years have opened some gaps facing the outside, which let lights and water come in.
Inside the cave they have found monkeys and flying foxes, and some scientists have discovered some species of plants which exists in Sơn Đoòng only.
The province of Quang Binh was one of the poorest of Vietnam, but after the discovery it has became one of the places where the turnout in tourism is amongst the highest in Asia. The region habitants have now the opportunity to develop a flourishing Tourist Industry, and the village of Phong Nha has quickly become the speleologists capital of South-East-Asia.
Below: view to the outside. Picture of Doug Knuth shared via Wikipedia – licence CC BY-SA 2.0
Below: three climbers on their way out. Picture of Doug Knuth shared via Wikipedia – licence CC BY-SA 2.0
Below: a video of an Exploration of the Cave