At Camp 1, there are no caves, but there is indeed a canyon and ropes: for want of thrushes, the team sets off to rig the driest part of the Poy canyon, which starts just below the camp. After rigging the 50 metres of cliffs that provide access to the bottom of the canyon and the first ledges already climbed, Christophe and Didier tackle the many small ledges that mark the route. Leaving a little later, Natalia and Franck take over. The site is magnificent, with some very steep sections requiring the use of our headlamps to progress. A final shaft forces the first of us to take a good bath, which, combined with the rain that is starting to fall, dampens our enthusiasm. The rest will have to wait for later.

This morning, Joash and Brendan were tasked with reaching the Galuwé riverbed from camp 1, taking the most direct path and without using ropes. They more than accomplished their mission: not only did they find the ideal route, but they also stumbled upon traces of an ancient settlement. Among their discoveries were two fragments of volcanic stone mortars used for grinding food. This also allowed them to stock up on an edible fern that grows in the site of ancient gardens and which is a very welcome addition to our diet, which is lacking in fresh produce.

At Camp 2, the decision is made to unrig the Mayang Eye, which appears to be nothing more than a large water basin. The anchors and ropes, which are beginning to run low, will be more useful elsewhere. Katia, Mehdi and Nicolas take on the task. The exploration of Ralapusa, on the other hand, is well underway, and Jean-Marc, Lionel and Denis make a first push downstream. Behind this large porch, a beautiful passage continues, which they explore for about 200 metres, accompanied by a strong and promising downward draft. Upstream of the sinkhole, Sylvain, Laurent, Elven and Michel cross several deep pools that complicate their progression, but here too, the future looks bright, vast and exciting. Fruit bats and salanganes accompany them noisily, giving their journey an epic feel.

Those who remained at both camps were not idle, by any means. Between the tedious tasks of treating drinking water, keeping logbooks, cleaning up the data collected, and all the other small tasks essential to the community, there was plenty to keep them busy.

The opening of an easy access route to Galuwé allows Christophe, Joash and Franck to consider moving upstream along the river, which flows at a rate of approximately 1.5 m3/s above Mayang, to the main resurgence that was spotted during the last helicopter reconnaissance. The idea is not only to see if it is accessible by caving or cave diving, but also to meet up with a team from Camp 2 consisting of Denis, Bernard, Nicolas and Mehdi, thus creating a physical link between the two camps. The descent is easy and the river is beautiful. After about two and a half hours of walking and cutting, they finally reach the resurgence. However, they are disappointed once again: the water seeps through the gravel and there is no passage to be found. The bubbles rising with the water suggest that the water comes from deep below. However, the site is magnificent, forming a large cirque bordered by numerous Filaos trees. This earned the resurgence its name of Lalu, the name of this conifer-like tree in the Mengen language. It is also a nod to Christophe, from Franche-Comté, the region where the Loue river flows, born from a karstic resurgence.

Radio contact is established with the team from Camp 2. They still have a long way to go before reaching the Galuwé. In the meantime, Joash, Christophe and Franck climb up the now dry bed of the Galuwé. A few ledges require gear, which is currently limited. A final obstacle that cannot be overcome without climbing equipment marks their terminus, not far from the section seen by Natalia, Joash and Franck on 2 February. On their way down, they finally meet up with the Camp 2 team downstream from the resurgence. Their descent, via a dry canyon, was more complicated than expected, requiring the use of ropes at several places. It's a happy moment when they meet up, and they exchange some supplies that were missing at Camp 1, namely tea and tobacco!

Meanwhile, back at Camp 1, Pita, Jerrica, Romain, Brendan, Carlos, Didier, Luc and Yann also descend to Galuwé, where they enjoy a refreshing swim and make new observations of the natural environment. On their way back up, they stop for a long time at the old village, taking lots of photos... and gathering ferns for their evening meal!

At Camp 1, a team is busy continuing their exploration of the Poy Canyon. Franck and Natalia set off to fetch equipment, Christophe begins surveying the terrain, and Yann follows the group, on the lookout for beautiful images. Beyond yesterday's terminus, a beautiful descent of nearly 20 metres leads to a very steep section occupied by hundreds of fruit-eating bats. The ledges then follow one after another until a beautiful dry waterfall over 20 metres high, where they have to improvise because they are running out of rope. One last ledge is equipped, then we have to stop at a final vertical drop. The resurgence seen by Natalia and Franck is still a good distance away, but we can hear the water flowing. Who will come and finish this beautiful canyon? In the meantime, we now have to dismantle our equipment.

Although Camp 1 did not offer us any caving objectives, we were able to explore the area thoroughly. Much of the Poy and Galuwé is now known, and the Mayang resurgence, a major karst phenomenon, has been well examined and documented. We can leave the area without regret.

At Camp 2, continuing the exploration of the downstream section of Ralapusa is obviously on the agenda. Lionel, Julien, Katia and Nicolas are tackling a series of deep pools, often requiring the rigging of guided abseils, which are time-consuming and require a lot of equipment. Although progress is slow, the future looks promising. Meanwhile, Laurent and Jean-Marc re-rig the access to the sinkhole and map it. These promising objectives make it possible to consider setting up an advance camp in the area to save time and energy, so Mehdi and Denis carve out a landing zone nearby so that they can helicopter in a big bag filled with the necessary equipment the next day. A perfect name for this forward camp, which will become the ‘Big Bag' camp.

The final days have come for the first month's team. On the morning of the 14th, they will leave the camps for Galuwé. At Camp 1, which will be dismantled for a destination yet to be determined, it is time to pack up. Everything must be prepared for the next day, and the bags must be sorted between those that will go to Camp 2 or 3, those that will remain in Palmalmal, and of course the belongings of those who are leaving us, namely Christophe, Didier, Romain, Pita and Jerrica. At Camp 2, those who are leaving, namely Sylvain, Mehdi, Nicolas and Lionel, are taking the opportunity to enjoy a last swim in the beautiful pools upstream from Ralapusa and a visit downstream to the point visited the day before.

At the same time, the next team is getting ready, stage by stage: Paris, Hong Kong, Singapore, Port Moresby, then the hassle of flights that never take off for Rabaul. Finally, after the ferry and a stop at Koki's Guest House, it's the last jump to the high-altitude camps.

Incidentally, the newly arrived members take advantage of this opportunity to purchase additional supplies based on orders placed from the camps (thanks to WhatsApp and satellite connections!): this is the last possible resupply before the end of the expedition and the final descent to Palmalmal, scheduled for 8 March.

From 7:30 a.m., a highly complex flight plan, finely optimised by Bernard to save every minute of flight time and implemented by the respective camp coordinators, is put into action. Like a musical composition, this manoeuvre involves more than 25 aerial movements. The challenge? Transporting the new arrivals to their respective camps, bringing the departing teams and their equipment back to the Galuwé DZ and, if possible, moving Camp 1 to a new area further upstream to better engage the teams towards the high plateaus of Mayang.

Bernard and Michel set off first to conduct an aerial reconnaissance. They quickly return to Camp 1 with good news: a suitable area has been found where the pilot agrees to drop off the first team. Carlos and Franck, who have remained on standby, climb into the helicopter armed with machetes and chainsaws and are flown to the area. The moment arrives when the pilot, hovering above an area of ferns and bamboo, shouts for them to jump. With no time to think, they hit the ground and immediately start clearing the area to allow access for the rest of the team and their equipment.

For six hours, the helicopter will make repeated trips between the three camps and Galuwé. It will be an almost flawless ballet, despite two trips where the pilot's destination errors will need to be quickly analysed and corrected on site. By mid-afternoon, everything will finally be in place for the second part of the expedition.

A torrential downpour hits both camps. At Camp 2, this means that within a few hours, all the water tanks are full, including the one-cubic-metre mega-box. However, the disastrous weather eventually causes the satellite connection to fail at around 4 p.m. The curtain falls!

For the brand new Camp 3, which still has no shelter, this rain is unwelcome! Especially since the higher altitude – this camp is located at over 1,400 metres – makes the area much wetter and colder than the previous camp. After extensive clearing and the felling of numerous trees, it is just possible to install a temporary tarpaulin over the brand new DZ to provide a minimum of comfort.

At Camp 2, a team of five (Michel, Denis, Katia, Julien and Bernard) set up an advance camp: Camp Big-Bag. Located just 25 minutes from the entrance of Ralapusa, it is next to a 400 kg store of food and equipment that was flown in by helicopter the day before. This strategic camp avoids a particularly steep and slippery 360-metre approach hike in bad weather. The objective is simple: to optimise exploration of the cave and its surroundings. The camp is set up in heavy rain, the team is soaked but ready to work, and the rest is postponed until the next day.

For Jessica, Tom, Bogdan and Laurent, the mission is different: Camps 2 and 3 are 3 km apart as the crow flies. A junction therefore seems possible and desirable. Especially for Thomas, one of the Papuans at Camp 3, who left his belongings in the helicopter. They were retrieved by Nolan, one of the Papuans from Camp 2. They set about cutting a trail to connect the two camps and realised, unsurprisingly, that the conditions on the ground would turn these 3 km into much more. For now, on this first day, they have managed to cover 2.5 km, which is already a significant achievement.

At Camp 3, the plan is clear: make things more comfortable! The whole team spends the day cutting trees. The area is difficult to work in, and setting up the large communal tent, which cannot remain on the landing zone, requires a lot of clearing and digging. Yann A and Anthony get the chainsaws roaring. Anthony cuts down a huge tree that would threaten the camp in the event of an earthquake or storm. The team also has to set up individual sleeping areas and install the antenna and generator, all in the pouring rain. By the end of the day, progress is evident, but the final installation of our communal area will have to wait until tomorrow.

At the Big-Bag advance camp in Camp 2, from 7am onwards, the team switches to ‘exploration site' mode, where every move is carefully calibrated: film sequences, photos and topography intertwine. Bernard leads the way, rigging more than thirty new anchor points in an area that requires both athleticism and finesse. He is followed by Katia in the rear, carrying additional equipment.

The progression becomes a real exercise in style: you have to juggle between rigging handrails and swings to avoid deep water areas and progression ropes to cross a few pits and obstacles. You move through a setting of organised chaos where giant pools alternate with spacious galleries.

One detail strikes the mind: enormous tree trunks are wedged high up in the ceilings, reminding us of the phenomenal power of the floods that can saturate this maze. Here, nature does not whisper, it roars with every downpour, and these natural witnesses remind us of this at every moment as we progress. For their part, Michel and Denis are busy with the cave mapping. Not a single detail escapes them, and everything is duly noted and recorded.

Jessica, Tom and Bogdan continue their challenging mission towards Camp 3. They make significant progress, stopping 350 metres away from the camp as the crow flies before turning back. The junction is near!

For Camp 3, it's time to get back to the comforts needed to continue exploring. Finally, the big tarp is set up in its final spot, and the kitchen, science, computer, and communication areas are organised. The two chainsaw whizzes cut big planks for a shared table, which gives Anthony a nasty case of tendonitis in his wrist. Finally, when evening comes, we can enjoy a good meal in a camp that is more or less set up, operational and comfortable. It was about time: fatigue and exhaustion are setting in for those who had worked to set up the two camps!

For the Big-Bag advance camp, the goal is ambitious: to reach the upstream side of Ralapusa via a giant canyon spotted a few days earlier by the reconnaissance team consisting of Jean Marc, Laurent and Nicolas, accompanied by one of our Papuan assistants. After two hours of progress through the forest, the team came upon a Dantean precipice with edges as impressive as they were unstable, a veritable break in the terrain. Bernard began to rig the wall, a rather ingrate and technical task: solid rock was rare, and there were many unstable areas, often hidden by lush vegetation. This unstable ground made each anchor point difficult to secure. After an hour and a half of vertical struggle, the verdict was in. At the top of a final, magnificent pitch, the view was breathtaking: a 70-metre drop plunged down to a large entrance porch. The measurements were extraordinary, confirming that we had indeed found the main drain of the system. But the reality of the expedition catches up with them: they have run out of equipment. Not a single bolt left, and not enough rope to reach the bottom. Frustrated but clear-headed, the team turns back, leaving the next team the privilege of a ‘first' that promises to be a great one! The walk back through the forest takes place in heavy rain.

For Camp 3, prospecting can finally begin. The camp is located between two large sinkholes, and the first objectives are obvious. A team consisting of Yann R, Patrick, Sophie, Natalia, and Franck heads towards the sinkhole to the east. The size is not too complicated, and the route is fairly obvious: just follow the stream bed that starts from the camp. As they progress, other thalwegs join in, and finally, after only 270 m of hiking and 60 m of descent, the team arrives at a beautiful vertical entrance carved out by a diaclase. A vertical drop of more than 25 m reveals a large void: finally, a beautiful hole! Exploration will be for the next day. The presence of numerous tree ferns around the cavity gives it its name: it will be the Gauunu chasm, the name of this plant in the Mengen language.

Tudor, Luc, Yann A and Anthony set to work on the second sinkhole. This one is more complicated to cut through, and as they progress, they realise that their steps are leading them towards the same sinkhole as the other team, to the point where they can hear each other. Although disappointed, this bodes well for the Gauunu chasm, which collects water from a very large area. They therefore continue their progress and head further west, towards an even larger sinkhole. They find several sumps, unfortunately without continuation, but a path is now open to a promising sinkhole area.

Mid-afternoon, heavy rain falls on the area. It will continue until late in the evening, making it the heaviest rainfall since the start of the expedition.

Early the next day at the Big-Bag advance camp, the relief team (Sergio, Bogdan, Jessica, Tom and Laurent) set off to tackle the upper section. They quickly covered the approach march and descended the sinkhole. On the evening of the 19th, news arrived by radio at Camp 2: the junction had been made! The 70-metre vertical drop had been successfully conquered, followed by 470 metres of galleries interspersed with pools, leading to the bottom of the Ralapusa sinkhole. It was thanks in part to the Squal Race hydrospeed that various stretches of water could be easily crossed.

Meanwhile, at Camp 2, it's war against electronics. Michel and Bernard are battling with the satellite antenna: assembly, drying each part individually, reprogramming, constant exchanges with technicians in Port Moresby. As a last resort, all the components spend the night in silica gel containers.

At Camp 3, it's time to go caving! Natalia and Franck set to work rigging the Gauunu chasm shaft, followed by Sophie and Tudor, under the watchful eye of Yann R and Luc-Henri's camera. Following heavy rain the previous day, a beautiful stream rushes into the cave and flood marks show that the water rose significantly during the night. The magnificent shaft is quickly descended. Unfortunately, things get complicated. The large volume at the base of the shaft leads to a more modest area cluttered with boulders and tree trunks, and it is necessary to squeeze through them to reach a small gallery partially filled with water. The traces of flooding are telling, and soon the main passage hits a siphon.

Other side passages are explored at the cost of crawling through mud and voûtes mouillantes (passages where the water comes almost to the roof), with only the top of the head visible. One thing is clear: the Gauunu chasm is not the big hole they had dreamed of. That doesn't stop Sophie from making numerous geological observations and Yann R from bringing back some beautiful images.

Meanwhile, Monika, Carlos and the two Papuans, Thomas and Francis, set off to cut a path towards the GPS point sent by Jessica showing their latest progress towards Camp 3. After cutting for about 350 m, they reach their trail. This means that the trail is now 5.7 km long: the connection between the two camps has been completed.

The next day, most of the team stays at Camp 3: there are still various tasks to be completed. Only Yann A, Anthony and Thomas set off to continue the path they had started to the north-east towards other large sinkholes. A few hours after their departure, a radio call came through to the camp: they had found a beautiful cave entrance and had managed to explore 250 to 300 metres of passages before being stopped, without the right equipment, by a small 9-metre-deep shaft. Could this finally be a great caving objective? In any case, the cave already has a name: it will be called Kosisilita, which could be translated from the Mengen language as ‘shared happy surprise'.

In the morning, Michel repairs the antenna. The miracle works: in less than two hours, the connection is restored. Camp 2 finally emerges from silence and invisibility!

During the day, the Big-Bag camp team joins Camp 2, and a new relief can now take place.

At Camp 3, it's time for exploration: almost the entire team will set off for Kosisilita Cave. Anthony, still suffering from tendonitis and a severe sore throat, and Patrick, who has a badly infected finger, will remain at the camp to recover. Thomas and Francis are tasked with joining Nolan and Augustin, the Papuans from Camp 2, on the connecting path. They plan to transfer some small equipment, including anchors for Camp 2 and Thomas's belongings. After about two hours of walking, the two teams meet halfway: the human connection between the two camps is established for the first time.

The Kosisilita cave does not disappoint. Between surveying, taking pictures, geological observations, collecting biological samples and rigging the vertical sections, things are progressing: behind the 9-metre shaft, the cave continues, quite large, and the stop is made in a gallery dotted with pools of water, where the echo of their cries resounds in the distance. It continues, and well, but one thing dampens their enthusiasm: traces of flooding are evident over much of the path, and if the cavity continues on the same pseudo-horizontal profile, progress will soon reach a critical point. But they are not there yet, and for now they are fully enjoying the pleasure of discovery.