Google Doodle honors world's largest cave Son Doong

Thursday’s Google Doodle celebrates colossal cavern Son Doong, a natural wonder officially discovered in central Vietnam in 2009.

The cave nestles deep within the remote jungles of Phong Nha-Ke Bang National Park, a UNESCO world heritage site in Quang Binh province.

Expert geologists estimate Son Doong was formed sometime between two to five million years ago, epochs before local farmer Ho Khanh inadvertently stumbled upon its enormous entrance in 1990.

It remained untouched until 2008 when Ho Khanh retraced his steps to its misty opening, and until 2009 alongside Howard and Deb Limbert of the British Cave Research Association. The intrepid speleologists conducted Son Doong’s first official survey and concluded that it was the largest natural cave on the planet.

Inside the cave’s undisturbed inner chambers, big enough to fit an entire city block of 40-story buildings, scientists discovered a wealth of record-breaking geological formations, including the world’s largest limestone pearls and tallest stalagmite, said Google Doodle.

Giant sinkholes situated further into the cave’s depths allow for sunlight and rain to nourish two pristine jungle ecosystems, which are home to flying foxes, the world’s only monkeys to live underground, and eyeless white fish, Google Doodle added. One of these thriving rainforests is so vast, it even has its own localized weather system.

In 2019, a trio of British divers proved there was still more to discover after finding an underwater tunnel connecting Son Doong to another cave, tacking on another 5.6 million cubic feet to its already titanic volume of 1.35 billion cubic feet.

Oxalis Adventure, in collaboration with the British Cave Research Association and the Vietnamese government, carry out expeditions to the cave.