This former French colony is a very mountainous Pacific island with a limestone karst of considerable potential. New Caledonia, the Loyalty Islands and the Isle of Pines have a karst area of over 2,000 square km.
Only a small fraction of the underworld has been explored and a hundred or so caverns have been listed, so there is much potential for further underground investigation. Some of the caves are accessible to keen tourists, as long as they are careful and respect the beauty of the sites. Others are reserved for speleologists with a penchant for adventure. Visiting caves usually requires the presence of a local guide and the need to bring your own lights. Many cave are on private or holy land, so remember to ask for permission from local authorities.
The karst landscapes of the mainland were formed about 60 million years ago. There are some important caves at Yaté.
The Touaourou caves have the curious feature of a vault pierced through by the roots of Banyan trees which form veritable curtains. They are easy to visit. You must simply ask for permission from the neighbouring tribe. Still in Yaté, a short walk along the coast leads to the entrance of the Wekou siphon and the impressive eddy which it causes at high tide.
Adio Cave L 6 km is the longest in New Caledonia. For more than 50 years, a Melanesian guide, Albert Gorodite, has been leading visitors into the bowels of the earth. He is easily found by asking at the Poya town hall. The main network follows a subterranean riverbed for about 3 km, which represents 3 hours of walking, before emerging lower down in the forest. The first 150 meters involves wading and is it difficult to avoid getting wet. This leads to the great gallery of the cave. It measures about 10 meters in diameter. In various places tributaries flow into the main stream, these are subterranean rivers yet to be fully explored. A visit to the cave is only for very fit people who are not afraid of getting completely wet through. The cave contains some very beautiful speleothems which are extremely fragile and very rare. Great care should be taken to avoid damaging them. There are numerous chambers, narrow corridors beneath dripping vaults, and at the end a fun labyrinth with a forced bath in very clear waters.
Situated 10 km from the west coast, the massif of Koumac covers a surface area of about 20 km² and its highest peak rises to 374 m asl. It is intersected by a canyon and the Koumac river and features two major phenomena: the Poultier hole and the Koumac cave.
The Poultier hole is a vast closed off depression 3 km long and 200 meters deep. Karst towers dominate this depression which constitutes one of the most beautiful landscapes in New Caledonia. Two riverbeds run through it: the "Great Forest" river to the west and the "Poultier River" to the east. WARNING: during heavy rainfall, these generally dry rivers are capable of receiving very large quantities of water, so you should not venture into them during flood times as the flow-rate can get up to 100m² per second.
The Koumac Cave. L 3.7 km The route is quite easy and the complete visit, to this very beautiful cave, takes about 3 hours. In December 8, 2000 the cave appeared on a stamp issued by the postal authorities.
The Kaala-Gomen massif covers a surface area of about 10 km². It has been very little explored and does not appear to contain a large system.
The minor karsts: Hienghène and Houailou These diverse karst areas are of small size and the caves found there are modest. The great hall of the Lindéralique cave in Hienghène, is worth a detour for its size and location. In Houailou, the little Nindhia massif encloses a cave of about 100 m long. It was explored in 1975 by Australians.
This island in the South province contains ten or more caves, most of which contain active underground rivers. Only a few of them are open to the public:
The Oumagne cave: it is possible to explore the first 200 meters, up to a small chamber that ends in a collapse. At the end you can find a flat platform which once served as a bed for Queen Hortense. At this point the river disappears underground and can only be explored by experienced speleologists who can continue another 1,000 meters into the Ouatchia cave : this site is taboo for some. This is where Queen Hortense supposedly hid before abdicating in 1883.
The Loyalty Islands are of great interest to cavers. It seems that caves were formed as recently as 300,000 years ago, when the sea level was 120 meters above its current level. Following one of the great events of our recent geological past, the glaciations, which had the effect of solidifying the ocean into ice, the lowest point was reached: 15,000 years ago when the sea level was 100 meters below the current level. Rainwater infiltrated the massif and ran out into the ocean, carving out passages at the same level as the that of the ocean. Each time the ocean level dropped, more caves were formed. It is these caves that are being discovered today. The deepest and most recent caves are therefore 100 meters below the current sea level. The rising water table which took place during the last fifteen thousand years was spectacular. The deepest caves were completely submerged and are now channels through which water penetrates inland.
On these coral islands, most of the caves are holy sites. Visiting caves is not a very well developed tourist activity. This has allowed the many limestone concretions that form fragile mineral sculptures to be preserved. However, informed tourists can visit some caves with a guide.
The island of Ouvea has 23 caves. They are of course difficult places to visit as they are not suitable for tourists. However, if you are an experienced cave diver, make sure you get customary permission and organise your transport and gear carefully.
The blue waterhole of Aben d'Anawa is located in the centre of the island, this is a cenote where rainwater collects and then forms two layers, fresh water and salt water. Anawa is the narrowest part of the isthmus. It marks the boundary between the districts of Fayaoué and Wénéki. The waterhole is home to a submerged forest at about 40 meters below the surface, at this point the underwater cave is 100 meters long and 60 meters wide. Another forest, this time of stalagmites and stalactites, proves that the island recently submerged and that the concretions and trees were able to develop in the open air before being drowned. Some of these holes are used as natural swimming pools by the children of the island, others shelter turtles.
The Lékine cliffs are situated 6 km south of Fayaoué. These high, grey, cliffs are riddled with caves facing the bay. Along the beach to the east, a pathway leads to the beginning of the swamp, between the stretch of sand and the cliffs.
The Cong-Ouloup cave can only be visited with the permission of the tribal chief, and also by undergoing the 'custom' rites. Legend has it that when the mainlanders invaded the island of Ouvea, the cave gave shelter to the gods of Canala. A track which leads to the top of the cliff offers a magnificent view.
It is in Lifou that the largest number of caves have been found. Out of 25 caves discovered, only 5 are open to tourists, and they can only be visited in the presence of a guide.
The Quajo cave in Qanono: to get there you have to walk through a forest. Coming out of the bushes in front of a greyish mass, you will find the entrance to the cave 20 meters further down. For those who want to go in, you will first have to swim along a dark corridor, carved out by the waters, before arriving in a natural swimming pool, surrounded by limestone terraces. This is where the dry cave begins. Watch out, you must follow the guide rope as you can easily get lost. Bring a waterproof torch so that you can admire the mineral sculptures found in each chamber. They are superb, some resemble beds of diamonds on the cave walls, others are called "the eccentrics" because of their strange crazy shapes, deifying gravity.
The Luenghoni Cave is only suitable for experienced cave divers. It is a flooded gallery more than 150 meters long and 30 meters deep. A true labyrinth, its many passages lead in all directions. You have to be careful following the guide rope. You plunge into the cold water then follow a lamp leading you to ever more beautiful chambers. The route leads past banyan tree roots falling into the water and stalactites reflected in limpid pools, you will also pass by fossilized shells. In the water are to be found eels and thermoclines, transparent fish with blind white eyes.
The Devil's Caves, are 5 km from the aerodrome and the path to the caves is clearly marked. Once there, you have to contact the guide and remember to bring a torch. These caves abound with legends. The Qanopeu Cave (meaning "entrails of the earth where spirits are born"), includes three chambers. The second of these, about 40 meters long, is home to bats. The third is the Devil's Bedroom with, at the back, a collapsed passage which used to lead to the sea.
The Xodre cave is between the cliffs and the sea, on the warrior route, is a cave you can visit.
The most elevated of the Loyalty Islands contains 14 caves including one of the largest underwater caves in the world.
The Bone de la Léproserie is a chasm which begins with a 50 metre well which, after climbing down a rope, ends up in a 40 metre deep lake. The entrance to this chasm only measures 25 meters in diameter, but the subterranean lake is 160 meters in diameter at its base. This is one of the largest flooded chambers, if not the largest, with 350,000 m3 of fresh water.
The Bone Hole or Hole of the Lion is a chasm 40 meters deep. The entrance is 45 meters in diameter. You can go to the edge of the circular cliff, in the middle of a tropical forest, and have a look down for hidden openings surrounding the dark-coloured lake. This 12 metre deep lake is unfortunately completely closed in and the gulf, at the bottom, reaches a diameter of 100 meters
The Pethoene cave is near the Médu tribal village, 50 meters from the roadside, follow the little track leading through the forest to find the cave.
Text by Tony Oldham (2003). With kind permission.