NN1 Diem Sinh 1
Development: 95, Denivelation : -15
In this area, a lot of entrances have been found, most of them didn’t continue very far. Khau Pang, flower cave, is an entrance of 15m high and 25 wide, but it is chocked after 20m. Diem Sinh 1 and 2 were the only caves that continued.
Diem Sinh 1 can be found at the end of a rice field, where a small doline continues into a gallery of average dimensions. Once an inlet is reached, a small lake is created. This active sump marks the end of the gallery.
NN2 Diem Sinh 2
Development: 959, Denivelation : -141
Coming from Tam Duong go through the small village and take a narrow path up the mountain till you reach the gigantic entrance porch. Climbing down the big boulders you get the impression the endless stream of blocks is chasing you. Eventually you reach the bottom of the entrance porch. Suddenly the sound of water appears coming from the gallery to the right though the water is invisible. The stream runs underneath the big blocks and boulders. Follow the big hallway, climbing alternatively over mountains of sand and mountains of blocks. At the bottom of the cave the stream appears. Follow the stream into a smaller hallway until the water suddenly disappears in a few small holes in the floor, not even big enough to pass you foot. We were startled by these small holes taking in such water. On top of that, the end of the cave is a big waterfall inlet (coming from the opposite side), which also flows in these holes.
On the bottom of the entrance porch you can also take a left to turn into a fossil, more horizontal part of the cave until you reach a large room. You can continue down trough a couple small passages until you reach a muddy siphon with some inlets.
NN3 Khau Lou 1
Development: 421, Denivelation : -40
The entrance of the cave is not far from the new road under construction that will connect Tam Duong to the north. To reach the entrance, one has to climb up from this road for several meters through the jungle. Although the entrance is not that easy to reach, local people sometimes use this tunnel shaped cave as a connection to the other side of the hill where they work in the fields.
The first entrance has a width of 6 meters and is 8 meters high. The gallery that follows becomes soon very big and 100 meters further it becomes that wide that it takes the dimensions of a large chamber : 60 x 100 x 25m high. The floor of this chamber is flat, with thousands of cave pearls scattered over the floor. All those pearls have dimensions up to 2 cm. Most of them are deteriorating. In the center of the chamber one can find a small, semi-permanent stream.
At the end of the chamber, one can climb a flowstone that connects the chamber with the second entrance of this tunnel cave. This entrance is more than 25m wide and very beautiful because of the sun shining through the vegetation.
NN4 Khau Lou 2
Development: 346, Denivelation : -46
The entrance of the cave can be found not far from entrance 2 of Khau Lou 1. In fact both entrances are very similar. This entrance is also a steep flowstone slope that leads to a big gallery. The floor of this gallery is also full of cave pearls, but these are very eroded and very big: some of them have a diameter of more than 15cm. This cave becomes very soon choked with another flowstone wall.
The morphology of both caves shows us that once they were connected and part of the same large gallery.
NN5 Khau Lou 3
Development: 100, Denivelation : -15
Walking further in the same area we found a very deep doline with steep slopes that lead to a river that disappears underground. We followed that river for some 100 meters, going down for some 15m. This underground river flows in a gallery that is sometimes high enough to walk, sometimes its only 80 cm high.
As is was the end of the day, we stopped in this third cave where we were standing up to the middle in the water. This cave continues! We will have to come back to survey this cave and to study the relationship with the Khau Lou 1 & 2 galleries.