“How couldn’t I be, since I knew that I would join an expedition to the biggest cave in the world for sure.”

Back in 2016, those were the exact words I penned as a young adventure consultant, fueled by the raw, electric excitement of stepping into the unknown. Looking back now, after more than a decade in the Vietnamese tourism industry, that untamed enthusiasm remains the compass of my career. Hang Son Doong is not just a destination; it is a living, breathing colossus that fundamentally redefines how you perceive our planet.

In this article, I invite you to step past the jungle curtain with me, journey back to the expedition that started it all, and discover what it truly feels like to stand in the heart of Earth’s greatest subterranean wonder.

Visited in Jan 2016.

Son Doong Cave seems impossible to me. I have dreamed of this trip since I first read about the cave three years ago when I was still in Ho Chi Minh City. But sometimes, the luck comes when we least expect it.

For me, I learned I would get that chance just 4 days before the departure. How could that be! How could an office girl who rarely works out, can’t swim and spend everyday concentrating on the screen to overcome 50km trekking  and caving in different terrain?

I was assigned to handle Son Doong bookings when my colleague Jamie took her maternity leave and Trung – another sales executive moved to another team. Proud and a bit nervous were my feelings at that time. Jamie had done her job so well that I was worried that I would not measure up. However, more than anything else, I was obviously excited.

How couldn’t I be since I knew that I would join an expedition to the biggest cave in the world as a part of the job?

I started to train. I got up 10 minutes earlier than usual, did push up, climbed stairs, jumped, squash and jogged sometimes. Actually, I  had just enough time to practice my daily workout. Staying up late at night and getting up early for work prevented me from completing the work-out schedule. So I decided to climb the 1,200 stairs up to Than Dinh Mountain every weekend. Luckily for me, I had just completed it once before I was asked to join the Son Doong pre-season trip. The decision was made on Jan 6 and the departure was on Jan 11, I had 4 days only for all preparation while most of regular customers have at least 6 months.

5 caving experts, two of their friends, two tour guides, 1 journalist, 1 ranger named Bach and a team of more than 10 porters were in our crew. Ah, me as well!!! The porters always did their jobs carrying equipment so I did not have chances to chit chat with them, but I talked with the chef and guide assistant.

I had heard and watched a lot about the cave but since now was my first time to visit it, I could not hide my excitement. My mom was worried when I informed her of my participation. I had to reassure her: “Don’t worry, Mom. There is only 1 guide and 2 caving experts for all 10 customers in a regular tour. Now  with 5 caving experts and 2 guides and with me, I will be safe and sound for sure”.

In the tour morning, I got up very early (I could not sleep because I was so excited). My Mom prepared sticky rice for the longest endurance of energy for my breakfast, I said good bye to parents to be in the jungle for 4 nights.

I was deeply impressed with the way the porters packed their bags. Their backpacks are PP woven sacks which were attached with the straps — the bright idea from the porters. Everything that you need for the tour was packed firmly and neatly: food, trekking gears, tents, sleeping bags, kitchen utensils and clothes. It was at least 35kg for each of them, some up to 50kg or even 60kg (like the water tank). How super they are! They all wore shorts and sandals, not long pants or boots (but the caving experts and tour guide would never encourage you to do that).

Being driven to KM35 on Ho Chi Minh Highway (Western branch) through Road Victory 20, we started trekking down to the deep jungle, across 3 mountains. We continued and crossed rivers 30 times. In fact, the water was just at knee level but the current was so strong. I successfully crossed the stream with a huge support from my colleague – a tour guide named Bao. We walked until afternoon to reach the entrance of Hang En. We stopped to set up headlights, put on the helmets and then headed to the campsite inside the 3rd largest cave in the world. From the high point on the rocky mountain, the tents at the sandy beach looked like yellow bugs. That was such an amazing view –one that I have been looking forward to for soooooooooooooooo long.

At the Hang En campsite – Day 1

Every day began with different dishes for breakfast and … coffee or tea!!! How luxurious this expedition is! With such the hard trekking and caving, people usually question “how can I survive?”. And this is how: We are served with hot coffee and hot tea in one of the most remote areas of central Vietnam, in the deep jungle and in a cave!

Hang En Exit – 2nd day in Son Doong Expedition tour

Each day is different. The second day inside the jungle was highlighted by the exit of Hang En, the descent the Son Doong entrance and the Hand of Dog rock formation. Visiting there, you will find out why Hang En was chosen for the Neverland gate in the movie Pan 2015. You will also hear the story of the cave’s 20-year discovery and rediscovery of the big cave, and the interesting stories behind the names Hand of Dog, Watch Out for Dinosaurs, the Garden of Edam. I was so lucky to join the trip with cavers who did the first expedition in 2009. Trevor, one of the members in that team, was the man who recorded those names in the book.

Watch out for Dinosaurs – Doline 1 – Son Doong cave

All the times I felt speechless and overwhelmed. It was breathtaking: after two days overcoming long trekking, river crossing and 80 meter descents, the Doline 1 opened up a new word for me with the” Watch out for Dinosaurs” area. Incredible! Fantastic! Unbelievable! Dozens of words came up in my mind but it seemed that they were not enough. I have been waiting for this moment for three years. I have seen this view hundreds of times in pictures and thought about it for several years; Now I saw it with my own naked eyes.  Everything appeared to me like heaven! I was there, at the middle of the biggest cave in the world, where the number of people who have visited is  fewer than those who have launched into space. I DID it! I WON! I did it by myself. I even could not remember what I shouted. All the poses for pictures I had planned suddenly slipped my mind. I was crazy with a repeated “yoga” position for different shoots.

We went ahead to visit with the Big Gour, the Wedding Cake (2 proposals have been made so far), the Reflection before reaching the Green Gour at Doline 2: the Garden of Edam.

Approaching camp 2 which is right next to the second collapse, we left our luggage there and walked to the Great Wall of Vietnam. In the dry summer, it is a muddy field leading to the wall. However, we visited the cave in January when the rainy season had just finished; and the muddy field was replaced by a large water body — a lake. We rowed the boats around 1km to the end of the cave – The Great Wall of Vietnam. In front of the high edge, my dream was just to climb up and conquer the wall.

It was really a once-in-a-lifetime journey to me. They way back was so nice with beautiful sunshine and gentle breezes. I had more chitchat with the porters, laughing all the way and happy with what I have done.

One target in 2016 achieved!

SOME NOTES FOR FUTURE ADVENTURERS:

• Prepare 5 pairs of sock: Use 2 pairs at the same time during trekking to avoid blisters.
• Take the sock off right after reaching the campsite, and dry your feet to avoid foot rot
• Bring as little stuff as possible. Your bag will get damn heavy when you are tired. Sometimes, you  don’t need to use it in the tour — but the porters have to carry it.
• Keep practicing by stair climbing before the tour. It is extremely helpful for the trekking over the mountains and hills.
• Put on a neon bright color shirt, you will stand out and be very eye-catching in pictures
• Pronounce correctly the name of Hang Sơn Đoòng /Ha:ŋ ʃɜ:n do:ŋ/, Not /ʃɜ:n du:ŋ/ please.

SOME UPDATES FOR 2026 SEASON

• The trip I joined was a setup tour before the first real departure started; the team member in a regular tour now included: 1 cave expert, 1 tour guide, 6 safety assistants, 2 chefs, and 18 porters carrying belongings.
• Oxalis is the sole tour operator to Son Doong cave. The only way for you to book the tour is through their official website.
• The expedition is currently fully booked for the 2027 and 2028 seasons. However, cancellations and last-minute openings do occasionally occur. We highly recommend contacting the Oxalis team or Endless Vietnam to secure your spot on our priority waiting list. Should a seat become available, we will notify you immediately so you can secure your booking if your travel dates allow.
• When I did the tour in early 2016, it was a 5D4N tour (2 nights in Hang En cave). Now the itinerary has changed: you will climb up the Great Wall of Vietnam, and you will stay in Hang En just 1 night.
• All photos in this article were taken by the team and myself, not by a professional photographer. The real scenery is much more breathtaking. You also can check the best Son Doong album here.
• If you found the Son Doong cave tour too strenuous and hard to book, there is an alternative for you to taste the 3rd largest cave in the world: Hang En Cave Adventure 2D1N