An article in the SCMP newspaper reviews the journey to discover the world's largest cave. During a trip to the forest in 1991, a farmer named Ho Khanh discovered the cave's mouth.

Vietnam's Son Doong Cave is one of the world's seven most beautiful underground attractions. (Source: VNA)

However, the sound of rushing water and strong winds made him afraid to continue entering the cave. The next times, he could not remember the location of the mysterious cave.

In 2007, when the British Royal Expedition conducted a search for a new cave in Phong Nha - Ke Bang, he took the team to search for the cave for two days, but did not find it.

By 2008, Mr. Khanh had found the location of the cave and contacted the British expedition team.

Through measurements, explorers confirmed that the cave is 5 km long. In addition to the underground river and lake system, the thriving jungle ecosystem, 400 million year old fossils and spectacular geological layers, Son Doong Cave is also home to a number of plant and animal species that exist nowhere else on Earth.

In 2018, a team of British cave experts discovered that Son Doong Cave is at least 30% larger and much deeper than previously thought.

In addition to Vietnam's caves, the list of the world's 7 most beautiful underground attractions also includes Tham Luang Cave (Thailand), Paris Catacombs (France), Cold War bunkers (Albania), Reed Flute Cave (China), Malinta Tunnel (Philippines) and the UK National Coal Mining Museum.