Diau - France
Trois Betas - Diau
We descended the cave at 5pm. It was quite late in the day, but we couldn't resist the temptation of a quick beer at the restaurant an hour back along the path. Our shocked fellow customers were glad to see the back of us - a posse of neoprene-clad cavers are not who you want to meet on a peaceful Saturday afternoon's stroll in the amazing scenery of the Haute Savoie. We had divided into two groups of 5 for the lengthy through trip from the Tete du Parmelan plateau to the Filliere valley, 700 metres below. This long anticipated expedition is described as 'probably the best caving through trip in France', and considering the French invented caving, it was definitely something to look forward to.
It started, as all good ideas do, in the pub! We were all looking for an adventurous caving trip to do in the Summer, so when Hugh suggested this 650m through trip we were all for it. Flights were booked, cars were hired - a trip was born!
Two months later, Hugh, Jan, Tim, Goaty and I relaxed in beautiful sunshine as the first group descended the entrance shaft - an 88m drop into the heart of the mountain. We decided to wait an hour to allow them to clear the first section of the cave before starting the descent ourselves. After a typical English Summer, it was great to have the warm sun beating down on us, especially in such an inspiring limestone landscape. Once our skin had turned a satisfying shade of lobster, it was time to go. I pulled my wetsuit over my shoulders, lobbed the rope down the small entrance pothole, and down I went. This was my first pull-through trip, and I was slightly nervous. A pull-through requires the cavers to pull the ropes down behind them in order to use them on the next shaft. Once the first rope is down, there's no way back up - in effect burning the boats. As Jan hauled the rope to join us on the small ledge I suddenly realised the only way out was 16 hours and over 5 km away. We were committed!
Disaster struck nearly straight away. At the bottom of the 88m shaft, I leaned on the rope to pull it down, but nothing happened. I put all my weight on it - not a budge. Tim came over to help, but even under the combined weight of the two of us, it still wouldn't move. This was the situation we'd all been dreading; the rope was stuck. We had to get the rope down, as it was needed further on in the cave, and there was no other way out. Tim volunteered to ascend back up the rope to discover the problem. He quickly discovered that the descent rope and the pull-down rope had managed to twist themselves around each other, Tim carefully untwisted them, then kept the well apart as he descended again to the floor. I once again leaned on the rope, a slight movement, then it stuck again, our hearts sank. But pulling harder it soon came free and the 70m of rope toppled down on top of me.
Another series of smaller pitches led to the biggest shaft in the cave, an exhilarating 58m free hang dropping into a spectacularly fluted chamber. A small stream entered from a tiny passage on the left, continuing onwards in a channel at the bottom of a large tunnel. We followed this in to a huge dry passage, coated everywhere with solid mud. The next section of the cave was just like an adventure playground. We swung on ropes above big drops, whooped along enormous train-tunnel passageway, ducked under massive waterfalls, and eventually ended up in the mammoth Salle des Rhomboedres. This chamber acts as a large collector for the three high altitude entrances to the Diau system. We could see where the shorter Bel Espoir entrance entered, but couldn't find the way on to the bottom. Panic ensued as we clambered all over the colossal boulders in search of it. Would we be stuck to wander the Diau system forever? A huge shout from Goaty led to relief by all as he found the route to the Puits des Echos, a large 39m shaft which did, indeed, echo. After a quick cuppa from the stove deposited by the previous group, we followed the water onwards.
We had now entered the Affluent de Grenoblois, a large streamway passage with glistening walls. The stone seemed to be reflecting our lights back at us. The many small drops and waterfalls adding to the excitement in the best bit of passage I've ever seen. We sped onwards and downwards in this winding passage - with everyone enjoying the route. It must have been past 3 in the morning, but the cave was too fascinating for anyone to notice.
A slowing and deepening of water indicated that the confluence with the Diau streamway was fast approaching. And though we all thought the cave had been brilliant so far, we didn't know the best was yet to come. The Diau river cave occupies a 5m diameter passage with a large, gentle river flowing through it. This passage of cave exposed another character to the all-encompassing trip: big passages, winding canyons, and now tubular river-passage; this cave had it all. We progressed easily along the tunnel, the water only knee-high, when we came across a large chamber with a tent in the corner.
This area had been used as a base-camp by the original cave-explorers. They had explored the cave from the bottom up, with the high entrances only discovered by intensive searching. We had our feed of noodles and Mars bars before pressing on in the cascading passage. The deeper sections of cave had wire ropes strung across the side. We clipped in easily pulled ourselves over the water. Jan and I zoomed off, being eager to explore this fascinating passage. It was only after we waited 10 minutes for the others to catch up that we realised there were problems. Goaty's acetylene light had failed early on, and he'd been using his electric back-up for much of the cave. That eventually ran out, and he was now on his spare electric, which was dimming rapidly. I lent him my spare electric - enough light to exit the cave, but not much more than that. This had slowed him down considerably, so we decided to stick together so he could cave by our lights.
The water was getting deeper now, with the strong current rushing past us. At one point we had a brief swim across a chamber, but we were still going strong and a quick look at the map indicated there wasn't far to go. Much encouraged, we stormed along the passage, leaving the river behind, we clambered down ladders, shuffled along thin ledges, waded through waist-deep pools before a glint of daylight could be seen in the distance. It was 9AM and we were back in the French countryside. I couldn't wait to strip off my wetsuit to bask in the sun once again, and the others followed likewise. Paul, from the previous group, was waiting with warm croissants and fine French coffee. We collapsed in the back of the car and returned to the campsite where we quickly sorted the gear before falling into a deep sleep.
The excellent Sunday lunch of endless beef and lamb eaten in the magical village of Thorens-Glieres topped off an excellent end to an excellent year's caving.