It was in the winter of 2001 that I came to Suiyang County and visited Shuanghe(Double-river)Cave for the first time. The French cave exploration team I guided consisted of six speleologists, several of whom were world-record keepers on the depth of explored caves.

Achievement Number 1: A 50-kilometer cave section mapped
It was raining when our car broke down on the way to Guihua. While we were waiting for help, I noticed there was a beautiful cave entrance not far away. Our tour guide told me, it was the Mahuang Cave and that a Japanese team had investigated it long time ago. It was not deep and not connected with other caves.

I need to explain here. A cave's lire is. Without exception, tied to that of a river. Shuanghe was originally a name for a surface river, so it was most appropriate to name the cave after the Shuanghe River that "gave birth" to it. The Shuanghe Cave has a complex cave system, and the Mahuang Cave, and some others mentioned later on, are" all parts of this complex.

Going along a small lane, I entered the Mahuang Cave. To my surprise, the top of the cave had some marks of erosion, showing that it had been formed by water infiltration．And it had obviously been used by humans before; there were some big stones lined up to deter people from entering. We detoured around them and found some discarded cookers and traces of mining of saltpeter. I continued walking. The path was very pleasant; a gust of cool wind blew at me and water dripping from the roof of the cave left many long water trails. 1 walked a few hundred meters further on. as far down as the point reached by the Japanese team. Suddenly I had this feeling: the Mahuang Cave was actually really important and we should investigate it more deeply.

The next day, we went to the Hongzhaozi Cave-a typical water cave. At the entrance there are two waterfalls and the walls of the entrance have been washed to a shine. Because the temperature inside the cave is fairly high, the water evaporates and forms long-standing fog．Soon，we arrived at a shaft and we lowered ourselves into it. I found another passage half way down and we all went into it and continued walking. As we walked we could hear water somewhere. Then, turning a corner, we saw a tiny waterfall.

The Hongzhaozi Cave is a water cave where the water inside never dries, while the Mahuang Cave was created by the water that used to flow into it. Then where had the water in Mahuang Cave come from?  And where does the water in the Hongzhaozi Cave go to? The Hongzhaozi Cave consists of three levels while the Mahuang Cave only has one passage.I guessed that the two caves must be connected.

The Shuanghe Cave is such complex and confusing place. At that time, we didn't know that it would be 85.3 kilometers long, the longest in China, the second longest in Asia and 20th longest in the world. All we had heard was that it was huge. One of the funs about speleology is that you can ask yourself questions，guess the answers and then go out and check them. But how could we measure such a huge cave? There was only one way, namely, section by section and solving the puzzle little by little.

So many questions put us into confusion, so we decided to stay in the cave for a while. After passing a huge, moist black rock, we reached a small cave within a cave"Jiejie Hall," This is only l00 meters long and 25 meters wide, and doesn't look anything special. But it has seven exits. And it supplied the answers. The subterranean stream in the Hongzhaozi Cave flows all the way here and cool wind follows it here too.

Jiejie Hall was the "Aladdin's Magic Lamp" for our investigation and we reaped undreamed rewards. That year,we mapped a 50-kilometer section of the cave, including the entire Huangma Cave and the l8-kilometer Hongzhaozi Cave, Pixiao Cave, Tuanduiwo Water Cave, Shanlin Cave, Longtanzi Water Cave, and also located the entrance of the Shuanghe Cave subterranean stream. This underground maze slowly revealed its mysteries to us.

Achievement Number 2: China's Longest Cave Identified Exploring the Shuanghe Cave was no easy matter. Sometimes, the floor was very muddy and slippery, and you could easily fall and get muddy all over; at places we had to go on all fours; at places, we would get stuck in narrow passages, unable to move forward or back; sometimes, we were up to our necks in cold water and practically had to swim to get across.

Despite the many difficulties encountered. We felt very satisfied. It is such a different cave-most tunnel. type caves have only one entrance and one exit, but the Shuanghe Cave has over ten.

The Shuanghe Cave has some mysteries, too. Walking up from one exit of the Jiejie Hall. we found a small hall where there were traces that stalagmites had been stolen; if so it seems as if the theft took place in remote antiquity since the path up to the stalagmites had disappeared a long time ago. We managed to climb up. We had thought ourselves the first to come here, but to our surprise, the ground bore prints of bare feet. These footprints seemed very old.

The spot was far away from the entrance. so I started thinking there might be another entrance, but on careful examination, my hypothesis was overtumed. It's not unusual to see some footprints at the enhance of a cave, but the way to this place is not only long but also very complicated. So how did they get in? Perhaps there had been  an entrance here previously that had perhaps vanished due to changes in the environment. I couldn't figure it out. I could only decide to leave these footprints as I had found them.

In the winter of 2003, we came to the Shuanghe  River again, but with a team twice as large as last time. Among the team were experts on karst and cave species. There are many living species in the Shuanghe Cave, the most common of which is a kind of white tadpole. They merit further study by specialists. Apart from the usual speleological ht of ropes, boats, cables and electric drills, we also brought fishing tools to investigate aquatic life and colored dye to better verify the direction of the subterranean stream.