Phong Nha, Vietnam
Son Doong Cave Expedition
- Length
- 6D5N
- How hard is it
- Extreme
- Group size
- 10
- Minimum age
- 18+
Only here: The largest known cave in the world, and this is the only tour licensed to enter it: roughly 1,000 permits a year, one operator.
Six days to the largest cave on earth: jungle trek in via Hang En, three nights camped inside Son Doong, out over the 90 m Great Wall of Vietnam.
What you actually do
- The largest known cave on earth by volume, at 38.5 million cubic metres
- Three nights camping inside the cave, one at Hang En and two in Son Doong itself
- A jungle and its own weather system inside the cave, under dolines 252 m deep
- Climb the 90 m Great Wall of Vietnam on ladders and fixed ropes to exit
- About 30 crew for a maximum of 10 guests: cave expert, safety assistants, chefs and porters
- Passes through Ban Doong, an isolated Bru-Van Kieu village in the park core zone
Is this the right tour for you?
Worth reading before you book. Age limits and group rules rule people out more often than fitness does.
Book it if
- You want the single biggest cave experience that exists, and can plan one to two years ahead
- You have genuine recent trekking form: their bar is 8 km days with 300 m of climbing, done recently
- You are comfortable with heights on fixed ropes: the exit is a 90 m climb
- Camping without showers for three nights sounds like part of the trip rather than the price of it
Look elsewhere if
- You want to go this year: departures sell out years ahead, so look at Hang En for the same valley now
- Anyone in your party is under 18 or over 70, which the operator does not accept
- The budget is a constraint: at 79,500,000 VND this costs nine times the Hang En camp
- You cannot commit to training: they expect you to run 5 km in 50 minutes comfortably
Day by day, all 6 of them
Arrive Phong Nha, briefing and gear check
Reach Dong Hoi by mid-afternoon and Oxalis staff drive you to Commander Lodge in Phong Nha. The evening covers the Phong Nha caves exploration museum, then the mandatory safety briefing: release form, medical declaration, shoe and pack check, and a welcome dinner with the group.
Trek to Ban Doong village and Hang En
A short bus ride to the trailhead, then a steep 350 m descent into the national park. Stream crossings lead to Ban Doong village for lunch, and three more hours of jungle bring you to Hang En, where you climb through the entrance to a huge sandy campsite for the first night. Guests who cannot manage this day can be turned back, a call the safety expert makes.
Into Son Doong, camp at Doline 1
After exploring Hang En's vast exit, the river route reaches the Son Doong entrance. Harness on, second briefing, then an 80 m descent into the dark past the Hand of Dog stalagmite to camp at the Level Playing Fields near Doline 1. There is an optional swim in an underground lake that sits at about 17 to 22 C.
The Garden of Edam
A slower day through passages and up limestone slopes on fixed lines to Doline 1, called Watch Out for Dinosaur, with lunch under the Wedding Cake stalagmite. The afternoon climbs into Doline 2, the Garden of Edam, a jungle growing inside the cave where the ceiling collapsed. Camp is set nearby.
Climb the Great Wall of Vietnam and exit
Depending on water levels you raft a lake or wade the muddy Passchendaele passage to the base of the 90 m Great Wall of Vietnam, then climb an 18 m steel ladder and roped ascents clipped to a safety line. Lunch at the top, exit the cave, trek out to the Ho Chi Minh Trail West and transfer to Chay Lap Farmstay for a celebration dinner.
Depart
Breakfast at the farmstay, then transfers to the airport or station in Dong Hoi, or stay on for Paradise Cave and Mooc Spring. Check-out is by midday.
What the price covers
- Pickup and drop off anywhere in Dong Hoi
- Full expedition crew of about 30: cave expert, guide, six safety assistants, chefs and porters
- All meals, tea and coffee, with vegetarian and vegan menus on request
- Commander Lodge the first night, three nights camping in the cave, Chay Lap Farmstay the last
- Helmets, harnesses, headlights and gloves
- National park entrance, environment and management fees
- Basic travel insurance as required by Vietnamese tourism law
Not included: extra food and drink outside the fixed menu, comprehensive personal travel insurance, which the operator recommends.
When to go
Runs January to the end of August. Closed September to December for the flood season, and the annual quota of roughly 1,000 permits sells out far in advance: at the time of writing the entire 2027 season was already fully booked.
Questions worth asking first
Can you visit Son Doong without a tour?
No. Son Doong sits in the strictly protected core zone of Phong Nha-Ke Bang National Park and independent entry is illegal. Oxalis Adventure is the only company licensed to run tours into the cave, and the expedition is the only way in.
How far ahead does the Son Doong tour book out?
Typically one to two years. Roughly 1,000 permits are issued per year and full payment confirms the place; at the time of writing the entire 2027 season was already sold out. If the wait rules it out, Hang En runs through the same valley and camps at the expedition's own first-night site.
How fit do you need to be?
This is level 6 of 6 on the operator's scale. Expect about 17 km of jungle trekking, 8 km of caving and up to 800 m of climbing, with recent overnight trek experience mandatory and a medical declaration at the briefing. Their stated benchmark is running 5 km in 50 minutes and five flights of stairs without getting out of breath.
Are there toilets inside the cave?
Yes, composting toilets in designated tents at each campsite. You can swim in underground lakes to rinse off, but soap and shampoo are banned in the water for conservation reasons.
What does the price include?
The 79,500,000 VND per person covers the full crew of about 30 staff, all meals, the hotel nights before and after, three nights of cave camping, safety gear, park fees and basic insurance. Transfers within Dong Hoi are included; getting to Dong Hoi is on you.
Is there phone signal on the expedition?
No signal and no wifi for the whole route, which runs through the park core zone far from roads. Guides carry satellite phones for emergencies. Treat it as a genuinely off-grid week.
How the price compares
Every tour here, cheapest first. Bars use a compressed scale so the shorter trips stay readable next to the expeditions.
- Tra Ang Excursion$30
- Phong Huong Adventure$50
- Elephant Cave and Ma Da Valley Jungle Trek$75
- Phong Huong Excursion$75
- Phong Huong Adventure Overnight$130
- Bach Ma Discovery$175
- Ma Da Valley Jungle Camping$200
- Victory Cave Expedition$295
- Hang Pygmy Exploration$305
- Hang En Cave Adventure$340
- Hang Tien Exploration$420
- Do Quyen Waterfall Top Adventure$435
- Hung Thoong Exploration$460
- Tiger Cave Series Adventure$480
- Kong Collapse Top Adventure$1,345
- Son Doong Cave Expedition$3,060
Approximate figures, per person; the operator bills in VND. Cheapest is 800,000 VND (about $30), dearest is 79,500,000 VND (about $3,060).
If this is more than you wanted
Jungle Boss
Kong Collapse Top Adventure
5D4NA 100 metre rope descent into the deepest sinkhole in Vietnam, over five days, with a medical check before you are allowed to book.
The only tour that descends the 100 metres to the floor of Vietnam’s deepest sinkhole.
Jungle Boss
Tiger Cave Series Adventure
3D2NThree connected caves and nearly seven kilometres underground, camping at the edge of the Kong Collapse sinkhole without doing the full expedition.
The only way to camp at the edge of Kong Collapse without committing to the five day expedition.
Jungle Boss
Tra Ang Excursion
1DThe cheapest way into a real Phong Nha cave: a short walk off the Ho Chi Minh trail, then a swim into the dark with a rope to follow.
The cheapest guided cave in Phong Nha, and the only one that takes children from age 7.
Photographs by Dave Bunnell, CC BY-SA 4.0, via Wikimedia Commons; Linhcandng, CC BY-SA 3.0, via Wikimedia Commons; Daniel Burka, CC0, via Wikimedia Commons.
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