Borneo is the largest island in Southeast Asia and actually comprises three countries. It consists of an Indonesian province of Kalimantan on the southern half of the island, the two Malaysian states of Sarawak and Sabah and the small oily country of Brunei. I flew from the uber-modern Changi Airport in Singapore to Miri in Sarawak, the city that is the sole gateway to Gunung Mulu National Park.
Gunung Mulu National Park is rather inaccessible for being one of Borneo's most famous tourist attractions and is reached either by a 30 minute plane flight or a 12 hour journey up river. The park is managed to standards unparalleled to other Malaysian national parks I have visited. There is an expansive boardwalk trail network through the jungle, a swing bridge canopy walk, several multi-day hiking options and many caves that are available to tour, both on and off path. The Park is incredibly proud of their status as a World Heritage site. The caves are unique in all the world, exceptional for their enormous size and unique fauna; it is also one of the most biodiverse places in the world. I saw countless varieties of insects (walking sticks, lantern bugs, giant crickets, fireflies, butterflies, bizarre caterpillars), geckos, snakes, pygmy squirrels, leeches, hornbills and frogs. The jungle is deafening with the sound of life. The amount of life in the caves was new for me. I almost put my hand on a hand-sized spider and another time I accidently cornered a racer snake in a small passage. At one point I had hundreds of bats swarming around me closely, but thankfully never flying into me. The cave swiftlets also darted past at close range, expertly echolocating in the dark by chirping.
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| Nepenthes (pitcher plant) |
The purpose of this trip was to be a tourist volunteer for the national park (along with some caving friends of mine) with the specific goal of mapping and documenting Deer Cave, which boasts one of the largest (if not the largest) cave passages in the world but previously has only been mapped in limited detail. We made very detailed sketches of the cave (showing formations, sediments, guano, rocks, trail and lighting infrastructure, etc.) to produce a map, collected thousands of data to make a 3D model, made observations on the geology and biology, and photo documented everything. In all, we spent a very busy week and a half in the cave.
Deer Cave is the Park's most popular tourist attraction so is easily accessed via a 3.8km boardwalk through the jungle. Butterflies, lizards and strange insects were frequently spotted en route to the cave. Deer Cave is huge! It is believed to be the largest cave passage known to man, although there is now a close contender in Vietnam. At the simplest description, Deer Cave is a giant tunnel through a mountain that used to be a conduit of a giant underground river. The 140m wide double-barrel entrance leads to an enormous passage 120m wide and 140m high. In the roof of this passage a hole continues upward with the faint glow of daylight at times. A laser shot determined this aven (or pit) to be over 1000ft high! This undropped pit is tied for the second deepest pit in Southeast Asia. The floor is covered in piles of ammonium-reeking, chocolate-colored guano up to 10m high and crawling with insects. A small creek flows in intriguingly from the eastern wall and straight ahead the lofty heights of the Antler Passage can be seen taking off into the darkness. The main passage then splits into a series of multi-level meanders until the active back portion of the cave is reached. In this back passage the Adam and Eve showerheads can be seen- unbelievable formations that drip water from the ceiling in a perfect ring. A underground river flows into the cave from a beautiful 145m wide entrance from the Garden of Eden, an enormous 1km wide karst window surrounded by vertical blue walls of limestone. The river flows for a ways down this large passage until it eventually sumps. Only 65m away it resurfaces in the furthest extent of Deer Water Cave where the river continues in 700m of younger river passage. We surveyed 4.8 km of passage in the Deer Cave System, but it is clear there is potentially much more if the upper levels are able to be reached and the big pit dropped.
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| Adam's Showerhead |
The theme of this trip was scale as my statistic-rich previous paragraph would suggest. These passages are so big the brain struggles to comprehend the distances. Even visual cues like a distant person seem warped. We would shoot a laser disto at a far wall or ceiling and frequently laugh at the large number we recorded. Because of the enormous entrances, daylight reaches over half a kilometer into the cave at the right time of day! In many places high-powered lights could barely penetrate the expanse. Our sketchers were frequently intimidated!
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| Look for the tiny people in the vast passage (and next photo) |
All told there were 11 of us, all experts in what we do. We typically spent the day working in groups of two or three on our particular tasks. I spent most of the time aiding a survey team by establishing stations, measuring inclination and azimuth, and measuring distances using a laser disto. I also sketched on the days when we were short of people due to illness or in places that the usual sketchers were not comfortable going. When there was free time, I explored leads in side passages, took photographs or documented the geology. A typical day had me leaving the cave about sunset, just as the millions of bats left the cave for their night feed. Watching the bats spiral out the entrance and then draw out into long snaking chains was quite a sight. Walking back entailed a great show of fireflies as the cicadas and frogs deafened the night.
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| Bats and moon |
Two of the survey days were standouts for me. One was the day I got to survey past the Deer Water low airspace to the sump. I donned a lifejacket and swam through the low airspace passage where water and ceiling are less than 15cm apart. Curiously the air is quite strong through this constriction, suggesting a connection to a yet undiscovered passage. On the other side, the river passage opens again considerably and it is comfortable walking and wading all the way to the sump. I had help quickly setting up a survey to the terminal sump, then spent the next three hours sketching on my own. While it probably was not the safest thing to do, I had a wonderful time caving in solitude. It was a good thing I finished the Deer Water survey that day as the following days it rained and the water level in the cave rose more than 2 meters!
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| A portion of the Deer Water sketch |
The other standout was the last day of the survey. I, along with one other caver, negotiated tight squeezes and many false leads through a breakdown maze in the back of nearby Langs Cave. We wandered around until, somewhat amazingly, we broke through a particularly tight squeeze and found ourselves in a draughting passage we both recognized. We continued on, popping out a hole where we greeted some of the rest of our group who were ecstatic. We were the first people to connect Langs Cave to Deer Cave. The rest of the day I took over the survey of the Antler Passage, the oldest and highest [barely] accessible passage in the cave. Getting up into the passage involves a greasy and loose scramble up a gully that most of the group was not comfortable doing. Once up, the passage has a real underground wilderness feel to it, unlike the rest of the cave. The floor of the main Deer passage can be seen over 100m down. All around are giant stalagmites to 30m in height and a bizarrely-corroded flowstone floor reminiscent of a underwater reef. The >60m wide passage climbs a hill and then drops down the other side of a ridge to where the passage appears to terminate at breakdown. The draft swirls mysteriously here. Several good leads remain and it is hoped that one will lead out to another entrance near the Garden of Eden.
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| >20m tall stalagmite |
Our survey was sketched at 20m to 1" and utilizes 26 cross sections and an astounding 1600 survey stations to accurately delineate the cave. The maps and 3D models remain to be made, but several useful statistics have come out of the work so far including at least 4.8km of passage in the Deer Cave System, a good understanding of the passage dimensions (huge!) and what is likely the second deepest pit in Southeast Asia. The back of the Antler Passage has a paleo-passage that has been filled by well-cemented breakdown that has since been dissolutioned by newer passage development, indicating the possibility of a very old passage here. The cave passages are strongly controlled by NE-SW-striking faults and, because there is relatively little collapse, a geomorphic history of the cave with at least 5 steps can be developed. In general, the active portion of the cave tended to migrate to the northwest (down dip) as base level drops. The reason the passages are so big appears to be because of the superposition of several individually large trunk passages. A large river passage migrated laterally into a preexisting subparallel passage, effectively doubling its size. The septum separating the "double-barreled" main entrance is an remnant of two former passages. The nature of the limestone (fine-grained, uniform, generally devoid of bedding and fractures) likely has inhibited the amount of collapse and allowed the passages to progress with limited self-destruction. The cave likely had a larger river than the one currently occupying it- this could be a regional scale effect of lowering base level, causing the underground waters to shift further NW through the Clearwater Cave System. Alternatively, the abandonment of Deer Cave could be linked to the formation of the Garden of Eden. An impressive record of sediments spanning the floor to ceiling will hopefully be cosmogenically dated to determine a detailed history of the cave's development. As always, there is still much to do!
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| Sketching (note trail in bottom left) |
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| Organizing the sketches |
One day was taken off to make the caver pilgrimage to the Sarawak Chamber in Good Luck Cave, the largest cave chamber known to man. Getting there required about 3 hours of jungle trekking on muddy trails and refreshing river crossings. I was miraculously spared by the leeches, but some of our group looked like they had been in a gunfight by the end of the day. The biting flies, however, did not take pity on me. The entrance to Good Luck Cave starts as a beautiful fern-encrusted, vertical-walled slot canyon that quickly becomes a 40m high passage with a flowing stream. The clear stream gradually deepens upstream and flows over sculpted limestone in a chain of waterfalls and pools. The water was the perfect temperature and unlike most caving I have done, I took every opportunity to be wet. The passage was sporty, requiring some fun climbing and swimming. One excessive pool measured about 10m in diameter with a 2m waterfall flowing into it. On the way out I found a spot to do a great 6m jump into the pool. After a while we abandoned the stream and began climbing a huge breakdown pile as the passage dimensions steadily increased. Before I knew it I was in the Sarawak Chamber- impressive for the inky blackness in every direction. The chamber dimensions are approximately 500m by 300m by 80m high! It is so big it has it's own weather! Mist filled the void. Best I know, all attempts to photograph the chamber have failed. After several silent moments of appreciation and awe, we returned the way we came. Pilgrimage accomplished.
The last few days at Mulu I took an enjoyable longboat ride up the river and hiked the 8km to Camp 5, the most remote camp established during a Royal Geographic Society expedition in the late 1970s. Travel was quick on the good trail apart from stops to admire hornbills and snakes. The camp is situated in a beautiful spot overlooking the river in the Melinau Gorge with its shear-walled, white-blue limestone cliffs pocked with enticing cave entrances. A refreshing swimming hole just upstream was utilized both day and night! The second day we got an early start and scrambled up the steep route to the Pinnacles. The last 200m was the most enjoyable as it was near continuous ropes, bridges and ladders. At the top is one of the most visually appealing landscapes I have ever witnessed. Fluted spires of blue limestone rise 50m from a vivid green jungle like a forest of stone. After a while fog rolled in which only added drama and mystique to the landscape. A very special place. Going down, energy and knees were saved by falling into trees and thus using my upper body as much as possible. It was here I got my first leech.
I flew into Kota Kinabalu in the Malaysian state of Sabah and ventured to Kinabalu National Park to undertake the two day hike up Mount Kinabalu, tallest mountain in Borneo at 4095m. It was here I ran out of Malaysian ringgit as nothing in the park takes credit card. Long story short, I would have been stranded were it not for the $30 NZ I happened to have stashed in my wallet. The park is way overdeveloped and touristy (though I could say the same of Yosemite and the Grand Canyon) and climbing the mountain involves a gauntlet of a mandatory permit, insurance and a mountain guide (i.e. glorified babysitter). The whole time you have to carry an ID tag and there are checkpoints you have to pass. I was assigned the oldest guide I saw on the entire mountain. I could have smoked him but chose to take my breaks when I could hear him breathing heavily. Even with photo breaks, we passed many a wheezing tourist and made it to the small alpine village of Laban Rata at 3000m in 3 hours instead of the usual 4-5 hours. The weather was great- the alpine air was the one respite in Borneo from the debilitating humidity.
The following day I took a ferry out to the small Sapi Island in Tunku Abdul Rahman National Park offshore Kota Kinabalu. Put me on a desert island and I will walk every square inch and make sure I understand the geology before I even attempt to relax. Mudskippers sunned themselves on rocks, glancing amphibiously at me, and launching into the water when I got too close. Gastropods were attached to the rocks in abundance and rolled off when they felt the vibration of my step. A 2m long snake and a 1m monitor lizard were sunning themselves on rocks. So life in abundance scampered with my every step. Apart from the landing area, I saw only one other person on my walk around the island. I chose the best beach on the island and alternated between reading, sunbathing and snorkeling in the crystal clear waters. The snorkeling was surprisingly good- I saw at least 6 types of coral, 30 species of fish, eels, vivid blue star fish, jellyfish and sea cucumbers.
My second ace is that people seemed to have quite a bit of respect when I told them I had spent about a week and a half volunteering for Gunung Mulu NP. The people took pride in their national parks and were delighted to hear about the cave mapping work. I am really drawn to the idea of vacations where half of the time is spent volunteering in some useful way- I'll have to keep it in mind for future trips.
Thanks are due to the friendly and competent staff at Mulu and my caving cohorts for a very memorable trip.
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| In the Sarawak Chamber |
Another day was taken off to do the classic Wind/Clearwater through trip, which despite taking less than half a day, was one of the best cave trips I have ever been on. The cave itself has over 175km of known passage and is currently the 9th longest cave in the world. It boasts one of the most incredible river passages anywhere. In terms of air volume, it is likely the largest cave in the world. Our trip started with a longboat ride upriver. The longboats are extended canoes that excel at the shallow riffled rivers in this portion of Borneo. There is a motor in the back that is pulled up when rocks or shallow riffles are approached. A man in the front then takes over to pull the boat up or down rapids with a long stick until it is deep enough to use the motor again. We went along the show cave path in Wind Cave to the nicely-decorated King's Chamber before leaving the path for some real caving. We did the classic route: Wind Cave Entrance -> King's Chamber -> Not Before Time -> Overtime -> Illusion Passage -> Wan Way Street -> King Seth's Maze -> The Battleship -> Clearwater River Passage. Most of the trip involved traversing a series of large chambers via up and down climbs and numerous slippery mud slopes. In two places we had to squeeze down tilted slots between a wall and breakdown blocks to continue on. The well-decorated chambers were nice, but easily forgotten once the Clearwater River passage was reached. Oh my God! This was a genuine underground river- one of the very finest in the world. It is 1.2km of pure, unadulterated caving bliss. The passage dimensions increase to about 40m in width with ceiling heights in excess of 70m. I floated, swam and jumped my way down the perfectly clear and cool river. The best jump I found was a solid 7m high. We were all giddy and did not want it to ever end. Just...words fail.
The last few days at Mulu I took an enjoyable longboat ride up the river and hiked the 8km to Camp 5, the most remote camp established during a Royal Geographic Society expedition in the late 1970s. Travel was quick on the good trail apart from stops to admire hornbills and snakes. The camp is situated in a beautiful spot overlooking the river in the Melinau Gorge with its shear-walled, white-blue limestone cliffs pocked with enticing cave entrances. A refreshing swimming hole just upstream was utilized both day and night! The second day we got an early start and scrambled up the steep route to the Pinnacles. The last 200m was the most enjoyable as it was near continuous ropes, bridges and ladders. At the top is one of the most visually appealing landscapes I have ever witnessed. Fluted spires of blue limestone rise 50m from a vivid green jungle like a forest of stone. After a while fog rolled in which only added drama and mystique to the landscape. A very special place. Going down, energy and knees were saved by falling into trees and thus using my upper body as much as possible. It was here I got my first leech.
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| Photo by Manuel |
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| Camp 5 |
I flew into Kota Kinabalu in the Malaysian state of Sabah and ventured to Kinabalu National Park to undertake the two day hike up Mount Kinabalu, tallest mountain in Borneo at 4095m. It was here I ran out of Malaysian ringgit as nothing in the park takes credit card. Long story short, I would have been stranded were it not for the $30 NZ I happened to have stashed in my wallet. The park is way overdeveloped and touristy (though I could say the same of Yosemite and the Grand Canyon) and climbing the mountain involves a gauntlet of a mandatory permit, insurance and a mountain guide (i.e. glorified babysitter). The whole time you have to carry an ID tag and there are checkpoints you have to pass. I was assigned the oldest guide I saw on the entire mountain. I could have smoked him but chose to take my breaks when I could hear him breathing heavily. Even with photo breaks, we passed many a wheezing tourist and made it to the small alpine village of Laban Rata at 3000m in 3 hours instead of the usual 4-5 hours. The weather was great- the alpine air was the one respite in Borneo from the debilitating humidity.
The most impressive thing of the hike was the stream of porters overloaded with "stuff" to carry up to Laban Rata. Mostly young men and older women, they typically carried their load with homemade backpacks (boards with straps) including a strap that went over their forehead for support. Some were friendly, others seemed to be living out a prison sentence. The porters were so constant and so overloaded with stuff, it was easy to think they would not stop until they carried the whole world up the mountain.
After a cozy night's sleep in Pendant Hut (which I had all to myself), the second day I began hiking at 3:15AM. My guide and I sliced our way through the hoard of slower hikers en route to the summit. It was colder than I thought but no trouble as long as we kept moving. Once the pack was passed, I turned off my headlight and enjoyed hiking by moonlight reflecting off granite slickrock. We were on the summit before 5:30AM to witness a wonderful sunrise and golden glow on the collection of peaks around us. It was a beautiful landscape but one awkward to photograph. The views were expansive. On the way down I met my guides to go down the mountain via the world's highest via ferrata, a trail of cable, iron steps and cable bridges across steep granite slabs. Beautiful views but the sense of exposure was lacking and the motion was really quite repetitive. We made good time returning to the trailhead.
The following day I took a ferry out to the small Sapi Island in Tunku Abdul Rahman National Park offshore Kota Kinabalu. Put me on a desert island and I will walk every square inch and make sure I understand the geology before I even attempt to relax. Mudskippers sunned themselves on rocks, glancing amphibiously at me, and launching into the water when I got too close. Gastropods were attached to the rocks in abundance and rolled off when they felt the vibration of my step. A 2m long snake and a 1m monitor lizard were sunning themselves on rocks. So life in abundance scampered with my every step. Apart from the landing area, I saw only one other person on my walk around the island. I chose the best beach on the island and alternated between reading, sunbathing and snorkeling in the crystal clear waters. The snorkeling was surprisingly good- I saw at least 6 types of coral, 30 species of fish, eels, vivid blue star fish, jellyfish and sea cucumbers.
Once back in Kota Kinabalu I had one (of many) Malaysian public transportation adventures to get to the airport to catch a flight back to Miri. I had to carry both of my bags on my lap so I effectively couldn't see anything. I spent the last two days in Miri taking day trips to Lambir Hills National Park and Niah Caves National Park. Lambir Hills boasted some nice jungle and abundant waterfalls falling freely over bedded sandstone. On a hike up to the Bukit Panto viewpoint I saw several pitcher plants and was ravaged by leeches. By the end of the day I had collected 5 leeches and my feet bled profusely.
Another Malaysian transportation adventure found me at Niah Caves National Park, site of archeological investigations that unearthed 40000 year old human remains. Painted Cave had 1200 year old cave paintings, which unfortunately have deteriorated greatly over the years. Great Cave was quite impressive- huge, wide fossil trunk passages straight through the hill with a network of bamboo poles and scaffolding hanging up to 200ft from the roof. Highly-skilled nesters free climb (without safety gear) up the poles to cantilevered platforms to collect the lucrative delicacy of swiftlet nests. A high-quality nest can sell for $1000 US per kilogram. Fatalities are not uncommon.
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| Great Cave (note the birder poles on the ceiling) |
During the trip I had two aces up my sleeve that made travel more enjoyable. One was that to the untrained Malaysian ear my accent was close enough to be a Kiwi accent. Some experimenting revealed that I generally got a much more favorable reaction and a longer, friendlier conversation when I said I lived in New Zealand rather than the United States. At times I felt a little ashamed saying it, but it was undeniable that the Malaysians thought quite highly of New Zealand. Many even had family that have emigrated to NZ or otherwise worked there.
My second ace is that people seemed to have quite a bit of respect when I told them I had spent about a week and a half volunteering for Gunung Mulu NP. The people took pride in their national parks and were delighted to hear about the cave mapping work. I am really drawn to the idea of vacations where half of the time is spent volunteering in some useful way- I'll have to keep it in mind for future trips.
Everywhere I went the Malaysian people were very friendly, particularly at Mulu. The climate was excessively humid for someone living in New Zealand but after a few days I began to acclimatize somewhat. I was really hoping to have a great trip but not too great- it is after all a big world and I have seen so little of it. Unfortunately, I have fallen for Mulu--its people, food, wildlife, landscape, caves-- and suspect it will not be the last trip I take to explore this special place.
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| Miri stilt houses |
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| Penan house at Mulu |
Thanks are due to the friendly and competent staff at Mulu and my caving cohorts for a very memorable trip.
*"Dr. Fu Yen's Mystical Earthly Paradise" is the name of a passage in Clearwater Cave. I have not been there but think it's a great name.
