Son Doong Cave Is Booked Through 2027 — How to See Phong Nha Now

On 30 March 2026, 200 international travellers logged on within hours of each other and tried to book Son Doong, the world's largest cave passage, in Vietnam's Phong Nha-Ke Bang National Park. All of them missed. The single licensed operator, Oxalis Adventure, confirmed that every expedition slot through 2027 was gone, and the earliest new booking now on offer is for 2028.

What actually happened

The surge traces to a CBS 60 Minutes segment filmed inside the cave 14-17 January 2026, which put Son Doong in front of a global audience for the first time at that scale. Oxalis caps the expedition at roughly 1,000 visitors a year — groups of up to 10 people with 30 support staff each, six days and five nights through a cave system large enough to hold a 40-storey skyscraper and its own jungle and weather. The going rate is about VND 80 million per person, roughly US$3,100. The cave itself was found by local farmer Ho Khanh in 1990 while sheltering from a storm, lost again for nearly two decades, and only formally surveyed in 2009 by a joint British-Vietnamese caving expedition that confirmed it as the largest cave passage on the planet — Oxalis didn't start running paid expeditions there until 2013.

If Son Doong was the only reason you were looking at Phong Nha-Ke Bang, the practical answer this month is: book 2028, or come this year for something else. There's a lot else.

What it actually takes to get a Son Doong seat

Even once 2028 dates open, a spot isn't automatic. Oxalis's own booking process runs in six stages: an online application with a detailed medical and fitness-history declaration; an automatic confirmation email; an application review that can take up to five business days; an approval email with an invoice and payment link; payment by bank transfer in USD; and pre-departure support once you're confirmed. The operator states plainly that the trip "is not for those with limited outdoor/trekking experience, those in poor medical condition, nor is it for children or expectant mothers," and expects applicants to show prior trekking, hiking or caving experience before approving a booking. Read that as a genuine filter, not boilerplate — the trek covers rough limestone terrain and river crossings, with two nights camping inside the cave itself and no way to shorten the route once you're in.

The cave you can still book this season: Hang En

Hang En is the antechamber to Son Doong — literally the same cave system, reached on the same trail, and the third-largest cave passage on Earth in its own right. Oxalis runs it as a separate two-day, one-night trek with camping inside the cave chamber, in groups of up to 16, priced at VND 9.5 million (about US$358) per person from 15 November 2026. The season runs December through mid-September and pauses for the wet months, so late-2026 dates are the ones on the table right now. Online bookings close at 19:00 the evening before departure, and the operator explicitly says it isn't for children, pregnant travellers, or anyone without prior trekking or caving experience.

Hang En doesn't need Son Doong-level lead time, but its own departures run only a few times a week and fill fast in the December-to-February peak. If you want a specific date, book it as soon as your flights are set, not once you land in Phong Nha.

No trek required: Phong Nha Cave and Paradise Cave

Two of the park's showcase caves need no expedition, no fitness test, and no advance permit — just a ticket. Phong Nha Cave, the boat cave that gives the town its name, costs 150,000 VND entry plus a 700,000 VND boat (shared across up to 12 people, so roughly 208,000 VND per person on a full boat), according to the Quang Binh tourism board's 2026 price list. Paradise Cave (Thien Duong), an 8.5-hour drive's worth of dry limestone galleries and one of Southeast Asia's longest cave systems, is 270,000 VND for adults, which now includes the round-trip electric shuttle from the car park to the cave mouth. Both are walk-up attractions that pair well with a single day trip out of Phong Nha town.

For something more active without an expedition-level commitment, Dark Cave (Hang Toi) runs a zipline-and-mud-bath package priced at 450,000 VND (about US$19) per adult, covering a 400-metre zipline crossing the Chay River, cave exploration by headlamp through 5.5km of unlit passage, a natural mud bath and kayaking, all safety equipment included, according to the operator's own 2026 pricing page. It runs 8am to 4pm daily and takes about 2.5 to 3 hours, making it the easiest half-day add-on to a Phong Nha or Paradise Cave visit.

Getting there

Dong Hoi Airport (VDH) is the gateway: it sits roughly 45 minutes' drive from Phong Nha town and connects with about 15 flights a week to and from Hanoi (around 1 hour 5 minutes in the air) plus routes to Ho Chi Minh City and Da Nang on Vietnam Airlines, VietJet Air and Sun PhuQuoc Airways. From Dong Hoi, taxis and pre-booked transfers cover the last stretch into the national park.

Staying connected in a karst national park

Vietnam's Ministry of Information and Communications reported in July 2025 that national 4G coverage had reached 99.8% of the population, with 5G still limited to roughly a quarter of the country and concentrated in the big cities. Phong Nha town and the park's main road corridor sit inside that 4G footprint; deep inside the cave systems themselves, obviously, there's no signal at all — Son Doong and Hang En expeditions are genuinely off-grid for the length of the trek. An eSIM installed before you fly means you land in Dong Hoi already connected, rather than hunting for a physical SIM counter at a small regional airport. Roameo's Vietnam eSIM plans start from US$3.49 and activate on arrival without swapping a physical card.

FAQ

Can I still book a Son Doong expedition for 2026 or 2027?

No. Oxalis Adventure confirmed on 30 March 2026 that every expedition slot through 2027 was fully booked; new reservations are being taken for 2028 onward.

Is Hang En a substitute for Son Doong?

It's a different, shorter trip on the same trail system rather than a substitute — two days and one night versus six days and five, with camping inside the cave chamber. It's the largest cave passage most visitors to Phong Nha will actually get to enter this year.

Do I need a guide to visit Phong Nha Cave or Paradise Cave?

No. Both are ticketed, walk-up attractions with marked paths and boat/shuttle services included in the entry price — no expedition operator or advance permit is required, unlike Son Doong or Hang En.

What's the nearest airport to Phong Nha-Ke Bang National Park?

Dong Hoi Airport (VDH), about 45 minutes by road from Phong Nha town, with regular flights from Hanoi and connections to Ho Chi Minh City and Da Nang.

Will I have phone signal inside Son Doong or Hang En?

No. Both expeditions go off-grid for the length of the trek — there's no cellular coverage deep inside the cave systems. Vietnam's national 4G network, which the Ministry of Information and Communications puts at 99.8% population coverage as of mid-2025, reaches Phong Nha town and the main park road, so you're connected again as soon as you're back above ground.