Zhang Fan (translated by Roger Yung)

Exploring deep inside unknown cave. Palawan is considered to be the best preserved islands in the Philippines. In 2011, the National Geographic magazine named it the world’s best place for scenic photography and diving. When our team first arrived at Palawan’s Puerto Princesa Airport, the first thing that caught my attention was an advertisement about the region’s caves and underground rivers. As a cave explorer, I was so excited. I said to the team, “Bingo, we hit the right target, because our whole team is now coming to explore these caves.”

Another member of our team who was even more excited was Jocelyn. She was excited because she was a native of Palawan returning to her birth place. Throughout our exploration she acted as our guide, interpreter and liaison officer.

Jocelyn works for How Man in Hong Kong, and so she knows that CERS has expertise in cave exploring. When she went back to Palawan on home leave, she chatted with her fellow villagers about How Man and the Society’s work. They felt that CERS could help them explore the many caves scattered around their villages and advise them on ways to promote tourism using these caves.

Aged markings on rock. On the plane trip, I made some comparisons between my home and Palawan. Kunming is an island plateau city and Palawan is an island on the sea. Kunming is 21,473 sq. km. in area and has a population of over 7 million people. Palawan is 11,785 sq. km. in area and its population is only 0.9 million. Both are popular tourist destinations. For a plateau person like me to travel to a tropical island, clothing preparation was extremely simply; a few T-shirts were all that was needed. If, however, a tropical person like Jocelyn were to travel to a plateau region like Kunming, she would need warm clothes which, after the trip, she would never have the chance to wear again.

Although Palawan and Kunming are different in many aspects, they have one thing in common and that is both are among the world’s most spectacular karst landscapes, harboring plentiful caves.

Caves are the cradle of civilization in both places. They are also a serious topic for study and research by anthropologists. In southwestern Palawan, a group of caves known as Tabon Caves are considered the cradle of Filipino civilization. Archaeologists have found prehistoric human bones and tools in these caves. Similarly, in the Longtan Caves in Kunming city’s Chenggong, archaeologists have also found human remains (known as the Kunming Men) and their artifacts dating back more than 30,000 years.

Spider with extended antenna. Kunming’s Luonan Stone Forest is world famous for its size and spectacular appearance and is listed as a World Heritage Natural Site. In Palawan, the place listed as a World Heritage Natural Site is not the beautiful Cockpit-Karst Landscape by the sea. It is the Puerto Princesa Subterranean River instead. Situated in Sabang, central Palawan, it is the longest known subterranean river cave system in the world, with a length of 24 km or more.

As an advisor of the Yunnan Tourism Bureau, I was impressed by the 40 minute boat tour along the Subterannean River, not so much because of the scenes along the underground river, but because of the high corporate ethics and management standards of the organization that runs the PPSR. While making efforts to attract tourists, the organization had not forgotten its duty to preserve the cave’s integrity.

Admission ticket for the PPSR was 200 pesos roughly equivalent to HKD30.00 per head which, I believe, is the about cheapest price for a similar place any where in China or Europe. So as not to disturb the bats and swallows nesting inside, no lights were fitted throughout the entire length of the river cave. The only source of illumination throughout our boat trip was the guide’s headlight. The guide was professional in his work and he was very kind too. He advised us not to look up with our mouths opened, unless we didn’t mind swallowing bat droppings.

Team taking notes. The next place we went was the nearby Ugong Rock Cave in Sabang. The cave, situated underneath a 100m high rocky hill, was in fact a narrow crack inside the body of the hill that extends from the bottom of the hill to its top. A few years ago, a local television station constructed two ropeways to the top of the hill to enable its crew to get there to film an adventure documentary. After the filming, local villagers used the rope ways to organize abseiling activities for tourists and the place then became a tourist attraction. Climbing up the whole length of the cave to get to its upper exit at the top of the hill was a tiring task. Not wanting to return by climbing down the same cave route, I decided to get down by the zip line. Bad luck for me and the long que behind me; there was a long wait, because the ropeway staff had difficulties finding a suitable harness for a Western tourist in front of us. He was at least twice my size, so the staff had to exercise extra caution when fitting the harness on him.

The next two caves we went to were the Hundred Cave and the Dinosaur Cave, which were not tourist caves, as they had hardly been explored.Their straightline distance from the Ugong Rock Cave was only a few kilometers, situated on two adjoining hills from the same mountain ridge. The hills’ white cliffs were very eye-catching against the green forests and farm lands surrounding them. Our team first arrived at a village near the caves. The village head and his assistants were already waiting for us by the side of the road. With Jocelyn acting as interpreter, the village head briefed us on what he and his fellow villagers knew about these two caves and other caves nearby. He said the land and use rights of these caves were owned by all the villagers together. They wanted us to help them survey and map them. They would also like us to offer suggestions on how to develop tourism, to teach them cave exploring techniques, and to help them train their people to become guides for cave tourism. These were all meaningful things that we could do for them.

Cave map drawn by CERS team. The entrance to Hundred Cave was about 94m in altitude and was only a short distance from the foot of the hill. This distance, however, was covered by a dense forest, and the forest floor was full of rocks with razor sharp upward thrusting points and edges. How Man’s footwear at that time was a pair of slippers, obviously not suitable and dangerous for walking there. He had to turn back, but the rest of us pushed on. The Hundred Cave was a system of branching caves with many entrances. That was the reason for its name. The cave system ran generally from north to south and comprised three layers, indicating that it was formed in different periods by crustal movement. The cave cavity was generally regular in shape and there were few formations such as stalactites inside.

Our measurements showed that the length of the cave was 461.2m, maximum ceiling height was 12.1m, and the biggest difference in altitude was 46.8m. While we were doing the measurements, Bill was examining the creatures we found in the cave with excitement. As a geologist, I explained to the villagers that accompanied us how things like stalactites were formed in caves. The team’s photographer, Xavier Lee, acted as my interpreter. The villagers listened attentively and with amazement.

Cave map drawn by CERS team. The last cave we explored in Palawan was Dinosaur Cave. It took us two days to complete the exploration. The entrance to the Dinosaur Cave was hidden in a cluster of rocks in the forest. This time How Man wore a pair of proper mountain hiking boots, however, I was still a bit worried about him. At one point inside this cave, the passage was very narrow and one could only barely pass through after taking off helmet and backpack. How Man surprised me when he safely passed through without great difficulty. On the first day, Zhou Chen Su and Wang Jian crawled through a very narrow crack in the cave to descend to an underground river. In a deep pool there, they saw a big fish, about 1m long and also some other smaller fish and shrimps.

The altitude of this entrance was 145m above sea level and was much higher than the cave itself. The cave comprised two layers; the upper layer was dry and the lower one was the underground river. As the dry cave on the upper layer was linked to the underground river at many points, ventilation inside the Dinosaur Cave was very good. Temperature inside the cave was a cool and comfortable 24.5°C. Outside the cave, the temperature was 34°C. Compared with the Hundred Cave, the Dinosaur Cave had many more cave formations and therefore had higher value for aesthetic reasons. As only very few people had ventured into the cave before, the calcareous deposits inside were largely undamaged. There were large numbers of bats, and also many cave invertebrates. In the cave I noticed an arthropod whose appearance resembled a combination of a spider and a scorpion. It had a big pair of princers which made it look very ferocious. I had never seen such a creature in China or Europe before. I subsequently did some research and now know that it is called a “whip spider”, belonging to the order of the class Arachnida.

Inside limestone cave of Sabang Cave. On our return to China, we quickly bought a batch of head lights for cave exploration and sent them to villagers together with the sketches of the caves we produced. We hope to be able to return to Palawan soon to help them train up people for cave exploration, as we have pledged.

CERS was not the first to do cave exploration in the St. Paul Karst Area. During our boat tour of the PPSR, I saw the words “1937 April 13” inscribed on the cave wall. Before we explored the Hundred Cave and the Dinosaur Cave, a total of 15 caves in the St. Paul Karst Area had been explored. The total length of these 15 caves are 30 km, and seven had a length over 500m. After our exploration of the Hundred Cave and the Dinosaur Cave, the number of caves in the St. Paul Karst Area that have been explored is increased from 15 to 17, and the total length of caves explored is increased by 1.3 km. For CERS, this is only the beginning.