Everything you need to know about Dark Cave

The Phong Nha- Ke Bang National Park in Vietnam is also known as the cave kingdom of the world! This explorer’s paradise has some of the biggest and most beautiful caves ever seen. Phong Nha-Ke Bang National Park is home to the largest cave in the world – Son Doong cave, the third largest cave in the world – Hang En cave, the cave made up of some of the rarest formations ever seen – Hang Va cave, the gorgeous Paradise Cave and many more!

Oxalis takes people on adventure tours into some of the most famous caves in the world in small groups in order to ensure a very exclusive and peaceful experience. On the other hand, Hang Toi or Dark Cave is more of a tourist attraction, which is suitable for families, friends and even children. Dark Cave or Hang Toi is one of the most celebrated and significantly touristic caves in the region and the Dark Cave tours is Phong Nha are considered to be top notch for backpackers and other travellers looking to spend a full day filled with adventure and fun! This is one of the best one day tours in Phong Nha and will surely be one of the most enjoyable experiences of your travel to Vietnam.

About Dark Cave


‘Hang Toi’, popularly known as Dark Cave, is one of the most major tourist attractions for people travelling to Phong Nha. This cave appeals to almost everyone that visits Phong Nha sheerly for the primitive fun that it offers. If you’re looking for a day out filled with adrenaline, fun and frolic, make your way to the Dark Cave. The Dark Cave tours in Phong Nha can be booked at almost any homestay, hostel or hotel in Phong Nha or just simply need to hop on a bike, follow the map and visit the cave by yourself. This is one of the best one day tours in Phong Nha, if you’re a fan of obstacle courses, swimming, kayaking, mud bathing, caves and zip-lining (Vietnam’s longest zip-line)!

If you’re wondering why this cave got the name ‘Dark Cave’, it’s actually quite self-explanatory. The whole cave has absolutely no artificial lighting system installed inside and once you’re inside you’ll also observe that the majority of the rocks are dark; primarily dark gray or black. Also, when you come out of the Dark Cave, after having an unforgettable mud bath, you will surely be darker than the cave!

Early Days

The Dark Cave was first discovered back in 1990. Soon after its discovery and exploration, the locals realized that it could be opened up for commercial use and bring worldwide travellers closer to Phong Nha – Ke Bang National Park in terms of the soft-adventure and natural thrill it can offer. Since the Dark Cave tours in Phong Nha started being operated, it has played a great role in terms of giving travellers a wonderful experience if they’re looking to spend a day out in the wild, filled with adrenaline and fun with friends.

Back in 2014, a decision was made to build a 400 meters long double zip-line which will serve as the apparatus to the entrance of the cave. This zip-line is known to be the longest zip-line in all of Vietnam and has also led to achieving a Vietnamese Guinness Record award at the Quang Binh province cave festival of 2015. All the early travellers that used this giant zip-line to access the the Dark Cave’s entrance called it one of the most adventurous and memorable experiences of their life, as zip-lining down above a river to an entrance of a cave isn’t something you get to do everywhere.

Geological features of the cave

You’ll get to experience the geological beauty of the Dark Cave with your whole body, as you make your way deeper inside the cave. The Dark Cave in Phong Nha – Ke Bang National Park is measured to be approximately 6 KM long. On your Dark Cave tour in Phong Nha, you’ll notice that the cave is primarily formed of crevasses that get narrower as you move deeper, muddy bottoms, thick clay walls.

The mud that you find inside is actually quite remarkable! The pattern, color and consistency of the mud inside the cave make it seem akin to pure chocolate milk. Another amazing part about the mud inside the Dark Cave is that it’s completely buoyant; you will not sink at any point during your adventure inside the darkness of the cave! The nature of the mud makes you float around rather nonchalantly and the mud-pits are considered to be one of the geological highlights of the Dark Cave.

When you explore the Dark Cave


The Dark Cave is considered to be an adventure playground for travellers also due to the features of the cave and how you get to be a part of it in true essence. For instance, if you’ve joined a Paradise Cave tour, you’ll notice that you get to walk to boardwalks and calmly admire the beauty of the cave’s formations with the artificial lighting system involved. However, the Dark Cave tours are quite the contrary. Here, it’s all about jumping in and being part of the adventure from the get go!

After you zip-line to the entrance of the cave Indiana Jones style, it’s time to put on your caving helmet (this will be provided to you by the management there). You’ll find a headlamp attached to your helmet and guided by its light, you’ll make your way barefoot through a crevasse that you’ll notice getting narrower as you continue. This steadily narrowing crevasse also gets muddier with each passing moment and eventually leads you to a section where you’ll be surrounded by thick clay walls on both sides and even underfoot.

As you keep moving forward, you’ll be welcomed by no trail at all and only deep and muddy footprints of the adventurer walking ahead of you. The whole little journey of 300 meters filled with squelching will surely be a really entertaining, funny and memorable experience for you. Please bear in mind that if you suffer from claustrophobia, Dark Cave will surely push you to the limits!

After making your way further, you’ll find that the crevasse you were clumsily traversing leads you to a giant mud pit. Once you get through all this, you’ll be invited by the cave’s cold river where you can enjoy swimming and de-mudding while reinvigorating yourself (in pitch darkness). You will make your way back by kayaking and to accentuate your overall experience, you also get to enjoy a special obstacle course over the water and even a flying fox! For many travellers, dipping in the jade blue Chay River on hot summer days is perhaps the most special part of this entire experience!

After getting done with your adventure, you can grab some grub at the Dark Cave restaurant where you can enjoy the traditional Vietnamese delicacies that’ll surely be an appetizing end to your adrenaline-filled day.

Please note that limited number of visitor can go in the cave for mud bath at a time, be prepared!

Visit the Dark Cave


The Dark Cave’s main entrance is located on the Ho Chi Minh Highway West and is around 5 KM north of the Paradise Cave; you just can’t miss the huge sign on a towering building that says “Zip-line to Dark Cave”. The tours usually remain open from 8:30 AM to 5:30 PM and you should wake up early should you wish to enjoy a full day of adventure, depending on whether you choose to do it solo or through a tour operator!

You can visit the Dark Cave with or without a tour operator. The prices vary, but so do the activities!

Pricing & Options


You can purchase entrance tickets and tours in arrival at the Chay River – Dark Cave Zipline & water sports center, or visiting the Phong Nha Tourism Center based in Phong Nha town or any homestays, hostels in Phong Nha and booking a full access tour with them.

There are three options for you to select:

Entrance & Swimming Options (No Ziplining, No Mudbathing)

Included: Entrance fee, swimming in the Chay river, water sports, safety equipment.

Excluded: Zipline, mud bathing, kayaking. 

  • Adults and children from 1.3 m in height: VND 80,000/ pax.
  • Children under 1.3 metre in height: VND 60,000/ pax.
  • Children under 1 metre in height: free of charge, only limited to the children’s swimming pool.

Full Access (Ziplining & Mudbathing)

Includes: Zipline (weight 40kg and under 90kg above), kayak, swimming,  water sports, helmets, headlamps, safety equipment.

  • Adults: 450,000 VND/pax (Low season only 250,000/pax)
  • Children under 1,3 metre in height: 150,000 VND/ pax (no zipline, sit on a kayak with their parents)

Limited Access (Ziplining, No Mudbathing)

Included: Zipline (weight 40kg and under 90kg above), Kayak, swimming, water sports, safety equipment.

Excluded: mud bathing in Dark cave

  • Adults: VND 270,000/ pax (Low season only 150,000 / pax)
  • Children under 1,3m in height : 150,000 VND/ pax (no zipline, sit on a kayak with parents)

What else to do in Phong Nha?

Are you looking for something else to do in Phong Nha, another easy-going, relaxing place or a real adventure in the Adventure Capital of Asia – Phong Nha?

Our What to do in Phong Nha page is what you cannot miss!

Or pay a visit to our Phong Nha Travel Tips page,we’ve listed some important things to know to help you make your way around our little town!


Kindly Note:

1. Oxalis Adventure does NOT offer any tours to Dark Cave. However, interested travelers can easily book the Hang Toi tours at any accommodation in town or simply head to their headquarter to purchase the ticket.

2. Oxalis takes no responsibility about the quality or service of the Hang Toi tours under any circumstances.

Oxalis Adventure Tours


If you are seeking a taste of the caves and really don’t have enough time then we recommend a one-day cave and jungle trek. We currently have three tour options for you to select, each with a slightly different style and suitability.

• Phong Nha National Park 1-DayOur family adventure in the Phong Nha offers a great taste of untouched jungle and impressive wild caves. It is the easiest level of adventure but there is still 5km of trekking and 2km of caving, and optional swimming during warmer weather into one cave. It’s suitable for kids from 12 and above with good fitness, and so this makes for a great day for everyone! It costs VND 1,650,000 per person (USD 72).

• Tu Lan Experience – 1 DayThis is one of our original one-day tours and still one of the best adventures in Vietnam. This one-day tour includes rock scrambling, 50m swimming through a wild river-cave, and up to 9 km of trekking through the lush jungles. You will also strap yourself in for a 15m descent down a ladder. It costs VND 1,800,000 (USD 78) per person.

• Hang Tien Discovery – 1 DayThis one-day tour is perfect for trekking enthusiasts eager to see the largest cave of Tu Lan but without time for the two-day experience. Hang Tien is a dry cave so no swimming required, but still includes up to 4km of trekking through mostly flat jungle and about 500m exploring this incredible cave that will no doubt impress with its grandeur. It costs VND 2,000,000 per person (USD 87).


Our most popular cave adventures start from two-days providing an immersive jungle and caving adventure, each targeting a slightly different kind of adventure-seeker, or perfect for those who want to combine a couple of tours to see different caves and areas on one trip to Phong Nha.

• Tu Lan Cave Encounter – 2 DaysOur most popular tour exploring the famous jungle area of Tu Lan. On this overnight camping excursion, you will trek through a number of different dry caves, swim up to 500m through a couple of river caves, witness outstanding cascading waterfalls underground as featured in National Geographic, and spend the night at our jungle camp beside a gorgeous waterfall. It includes 12km of trekking and 3km of caving in total and is for those with a good adventurous spirit. It costs VND 5,500,000 per person (USD 239).

• Hang En Cave Adventure – 2 DaysFor two days, this is our best-value-for-money tour that includes one of the most jaw-dropping natural landscapes you will see in this lifetime. This cave is considered the second largest cave in Vietnam and third largest in the World, and it also makes up one night of the original five-day Son Doong Cave Expedition being so close to the largest cave in the world. It includes visiting Ban Doong Ethnic Village, located in the jungle, and a magnificent campsite on a sandy beach inside the cave. It includes 22km of jungle trekking at times quite rocky, multiple knee-deep river crossings, and elevation change of 400m (the ‘hill’ you won’t forget), and 4km of caving. This is a level 3 adventure on a scale of 1 to 6. It costs VND 7,600,000 per person (USD 330).

• Hang Tien Endeavor – 2 DaysA two-day trek into the jungle to see the largest dry cave of the Tu Lan area, exploring 5.5km of this truly stunning cave, with a variety of karst formations. This 13km trek is suitable for those not too keen on cave swimming or too many hills, but still up for an adventure. This is a level 4 adventure between 1 and 6, with 6 being the most challenging. It costs VND 6,500,000 per person (USD 283).

• Hang Va Expedition – 2 DaysA technically challenging, but equally rewarding two-day caving adventure in the heart of Phong Nha National Park. This tour takes you deep into the jungle to one of the most spectacular river-caves, with formations not seen anywhere else in the world! It involves rock scrambling, wading through an underground river, bouldering and rope-traversing within the cave, to reach the rarest tower cone formations. This involves quite a lot of technical work due to safety, but is not overly difficult, it includes 10km of trekking and 3 km of caving.  This is a level 4 adventure, with 6 being the highest. It costs VND 8,000,000 per person (USD 348).


Now, if you really want to increase the adventure and soak up the wild jungle of Vietnam, with plenty of time to relax and enjoy the area, we highly recommend a three-day caving tour of our Tu Lan or Hang Tien.

• Wild Tu Lan Cave Explorer – 3 DaysThis tour incorporates the very best of Tu Lan with two different jungle campsites besides stunning waterfalls, 3km of cave exploring through a number of caves, 1km of cave swimming and visiting some additional areas not included on our shorter experiences. Our three-day tour is very popular and tends to be booked out so get in quick to enjoy this thrilling jungle adventure. It includes 17 km of jungle trekking and with quite a bit of swimming you will need to have a good level of fitness. It is not for the faint-hearted, but still only considered level 3 adventure level compared to level 4 of the Hang Tien 3-day tour. It costs VND 8,000,000 per person (USD 348).

• Hang Tien Exploration – 3 DaysThis three-day tour stands out for combining a taste of Tu Lan with some river cave swimming, before crossing a mountain range to reach the valley for Hang Tien – the most astounding dry caves in the region, where you will enjoy trekking, bouldering over various rocky terrains to witnessing breathtaking patterned calcite walls & ceilings of Hang Tien. It’s challenging and definitely more suited to adventure enthusiasts who have trekking experience and prefer more challenging routes. It includes a total of 22km of trekking, 6.5 km of caving and an elevation change of 150m over one particular hillside. You will get wet, you will be challenged, but you will not be disappointed. Hang Tien is located adjacent to the Tu Lan area so you will enjoy the best of both worlds – a level 4 adventure out of 6 adventure levels. It costs VND 8,500,000 per person (USD 370).


For those looking for the ultimate adventure experience in Vietnam, and thriving for the real grand expedition of the world, you should opt for these 4-day journeys to explore the entire cave system of Tu Lan and the largest cave on Earth

• Tu Lan Expedition – 4 DaysYou will also explore all of the extraordinary caves in Tu Lan, including Kim Cave and Secret Cave that boasts phenomenal natural falls and karst formations inside these two unbelievable river caves. Complete a trek through Hang Tien Cave – famed for its vastness and magnificent formations. Our secluded jungle campsites are spectacular and mostly different from those visited on our shorter treks in the same region. This is a perfect alternative expedition for those who are unable to do Son Doong Expedition, still it’s challenging and not recommended for those without experience. It includes an additional night at Chay Lap Farmstay before the tour to ensure you are well rested and ready to depart early the following day. Level 5 on our 6 adventure levels. It includes 30km of jungle trekking, 5 km of caving, about 800m swimming through caves and one abseil in a cave in the pitch black – highly adventurous! It costs VND 15,000,000 per person (USD 652).

• Son Doong Expedition – 4 DaysBy now you would have seen some pictures of Son Doong Cave, and even they don’t do it justice. The record-breaking Son Doong Cave is hands-down one of the most stunning places on this planet Earth. The expedition is tough, but not too difficult so long as you have a strong resolve to achieve. It is surely one of the newest wonders of the world. Son Doong is not just another cave tour – it is life-changing to say the least. It includes 25km of trekking, 9 km caving including rope climbs, and the 90m ascent of the Great Wall of Vietnam using a ladder, elevation change of 400m and many river crossings inside and outside the cave. Level 6 on our adventure levels. It costs VND 69,800,000 per person (USD 3000).

STILL HAVE QUESTIONS?  Visit our FAQs section where we have a lot of answers for your questions and concerns. https://oxalis.com.vn/faq-general/

WANT TO SEE VIDEOS OF OUR TOURS? Visit our youtube channel at https://www.youtube.com/user/OxalisAdventurTours

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