The 2017 trips, on sale on the website of Oxalis Adventure Tours, the sole operator, will offer five-day and four-night tours with a maximum of ten people at the cost of US$ 3,000 per person during the January-August period.
Each tour requires a team of 25 porters and cooks, a tour guide, two cave experts and two park rangers.
Visitors need to ensure they are in good health before embarking on the adventurous trip. People who suffer from high blood pressure, cardiac disease, joint problems or diabetes are not eligible for the trip.
According to Oxalis, the company welcomed 442 visitors in 2016, including ambassadors from Argentina, Sweden, Italy, the UK, Australia, and the Czech Republic to Vietnam, US Assistant Secretary of State Tom Malinowski, the second runner-up of the Miss Universe Viet Nam 2008 Truong Thien Ly Duong and Vietnamese ambassador Pham Sanh Chau.
Oxalis, based in Phong Nha-Ke Bang National Park in Quang Binh Province, has been organising tours to Son Dong Cave since August 2013. Oxalis has often sold out their limited tours well before they start. Tours in 2016 were sold out by August of 2015.
Son Doong, which is 150 metres high and 200 metres wide, became known worldwide in 2009 when it was explored by members of the British Cave Research Association led by Howard Limbert and his wife Deb Limbert, guided by local resident Ho Khanh.