Supposedly, a Boeing 747 could fly through the cave without damaging its wings, but that doesn’t really do justice to the true vastness of Son Doong. The stalagmites here are pretty massive too, with some reaching up to a whopping 70 metres, writes the article.

Son Doong cave was first discovered in 1990 by Ho Khanh, a local man in Phong Nha town of Bo Trach district in Quang Binh province. It was later announced as the largest cave in the world with a volume of 38.5 million cubic metres, following exploration trips by the Royal British Cave Association.

The cave stretches for nine kilometres long and is punctuated by two huge ceiling collapses which invite in natural light to pour into the cave.

Son Doong is located in the heart of Phong Nha-Ke Bang National Park and is a UNESCO World Heritage Site. It first opened to tourists in 2013.

The cave system includes at least 150 individual caves, a dense subterranean jungle, along with several underground rivers. British magazine Conde Nast Traveler named Son Doong as one of the seven must-explore wonders of 2020.

Son Doong cave tour is currently considered to be the most expensive and attractive tour in Vietnam with a ticket priced at about VND72 million, equal to US$3,000, per person for a six-day and five-night tour. Each tour is made up of 10 visitors and about 30 supporters serving as cave safety experts, guides, safety assistants, chefs, and rangers, whilst others help to carry luggage, food, and camping equipment.

Mammoth Cave in the United States tops the list of the 10 best caves in the world as compiled by Timeout. It is followed by Škocjan in Slovenia and Waitomo Caves in New Zealand.

Son Doong cave ranks sixth, above Reed Flute Cave of China which is also known as the ‘Palace of the Natural Arts’.