Hang En – the third largest cave of the world

Hang En – the third largest cave of the world

Two years ago when I made a little research preparing for my first Southeast Asia trip, the Phong Nha – Ke Bang National Park and its multiple day trekkings already made it to my list. That time I never got to Vietnam at all. But when I started to plan this trip, I remembered that I really wanted to see this beauty. The largest cave is not available for me for obvious reasons (the 4 days trekking costs 3.000 USD), but there were still some options left.

At the moment there are 3 adventure companies organising tours to the caves and in the park, all of them have different offers. Every cave is maintained and used by only one company. Oxalis is the oldest and most experienced company, its guides are trained by the British caving experts (same guys who worked in Thailand in the famous rescue mission), and they are the ones serving Hang Son Doong, the largest cave. The Jungle Boss once worked for Oxalis, now organising tours among others to the fourth largest cave of the world, to Hang Pygmy. And there is Phong Nha Discovery with smaller tours. So there are many options out there, but what is common, there’s basically no 2 days tour under 7 million VND. I was thinking a lot about having such an expense, but my heart said yes, I only had to decide which one to choose. I was watching videos at home already, showing it to family and friends, dreaming about being there. Still, I didn’t book anything as I didn’t know when I get there.

I found an Oxalis office when I was in Hoi An, so I just went in checking on my options. There were two treks on the dates when I supposed to be in the park, but it turned out, that someone just cancelled the Hang En trek on the dates that suited my schedule. This is one of those treks that gets booked out months ahead. I felt this was a sign. I still needed some time to give it a thought as I knew that this cave is not particularly rich in formations, instead it is huge and it is a unique experience to camp in the cave. I decided to join in and emptied my bank account with just one movement.

To all the tours booked in the Hoi An office, Oxalis gives a complimentary bus ride to Phong Nha either from Hoi An or from Hue. This can be used days before the trek as well, so this is exactly what I did. I had nothing else to do just to be ready in the morning of the tour and let the Oxalis people pick me up.

During the trek to the entrance of the cave we cross 15-20 streams and rivers, then again on the way back. (Hereby I ask my hiking friends who know my relationship to river crossings very well, not to laugh too much.)

Waterproof and goretex shoes are not the best for this trek, as after the first crossing when we are in the knee high or waist deep river the shoes get soaked and heavy and it is not much fun walking in them anymore. I got a pair of simple canvas army boots, a semi-dry bag and a water bottle, and I only needed to carry the essentials for that very day. Everything else was carried by the porters, together with all the camping gear.

Fun fact, that the tour guides wear plastic sandals while most of the clients bought high end trekking shoes just for this trip. Their plastic sandal is the renewed version of the model wore by the viet cong during the vietnam war. This is a simple 1 dollar plastic item, that was slightly redesigned by Gucci a couple of years ago and sold for 500 dollars per pair, keeping my tour guides laughing ever since.viet cong sandals

Just before we started we got a short briefing, safety instructions and checked the required items list for one last time. Left the unnecessary stuff together with the passports to have them locked in the office, and started our 30 minutes ride to the starting point. We walked about 10-12 km that day. The only difficulty was the slightly slippery terrain and the leeches that tried to find their way to our skin. We found a green viper as well, but I guess I was the only one who took the safety instructions – don’t take photos especially no selfies and slowly back off – seriously, so I actually can’t show it to you.

The reward after the jungle trek is the view at the entrance of the Hang En cave. The guides take insta compatible photos of everyone: pose 1-2-3, another pose, turn back, look to the right… everyone happy. The cave itself is really huge. The entrance arch is 100 m high. The entrance collapsed about 2000 years ago, and we are posing on top of the debris. We enter through a small side entrance, and take a raft to get through the pond to our campsite.

Four of us went swimming in the super cold pond, but honestly, the other’s approach of ‘I only go if you go’ did not help me much. I thought about my friends who jump into freakin’ cold mountain rivers to swim without hesitation, and with a small course on my lips I jumped into the pond. The others followed in about two minutes. Well, the temperature and the feel of it didn’t get better by the time, so I came out in a short while. It got dark pretty soon, so after dinner most of us went to sleep right away (the rice wine was not attractive enough). I listened to the noise of the birds before falling asleep.

Next day we went deep into the cave to explore. There are not many stalactites/mites, but the structure of the cave, the fossils and growing formations and the sites familiar from the Hollywood movie Pan are all super impressive. The cave is about 2,8-3 million years old and they believe it was part of Hang Son Doong, the largest cave of the world. After a collapse they separated and and now its entrance is 3 km away from Hang En. While the Phong Nha-Ke Bang National Park contains the oldest karst system in Asia, between 400-450 million years old, Hang En owes its relatively young age to its location on the edge of a fault zone. The ‘largest’ is not measured in depth or length, but by the volume of the cave. The entrance hall of Hang En in 100 meters high and 140 meter wide, at some point the chamer is 100 meters high and 180 meters wide. Hang En stretches over 2 km deep into the karst mountain. The cave is flooded by the Rao Thuong river every year, constantly eroding its walls and widening the cave itself.

Once we played enough with the lights, posed in the gigantic halls and tried to escape from the bat poop raining from the ceiling (holy shit, as our guides call it), slowly we headed back to civilisation. We chose a partially different route, yet still with a lot of river crossings and with a steep 40-50 minutes climb at the end. We finished the day with opening the cold beer appearing from the bus and with great smiles.

The team of Oxalis is really professional, they use excellent gear, provide Petzl caving helmet and Petzl head torch, canvas army boots if required (size EU 36-46), tents, comfy sleeping mat and sleeping bag, porters to carry all these, warm meal, the chef, the guides speaking excellent English and trained by the British caving experts and safety personnel for the jungle trek. I think the trek itself is slightly overpriced, but the experience is truly unique and the company actually owns the monopoly, so if you desire to see one of the largest caves, you got to be served by a great company.


  • Oxalis Hang En 2 days/1 night trek, full board, group of 16: 7.600.000 VND (330 USD)