Part I: The caves system

Résumé - Abstract - Zusammenfassung :This first part is divided in four chapters and describes in detail results of our explorations. The four counties visited on the right bank of Yangtse river are the counties Wufeng, Hefeng and Xianfeng of Hubei Province and Sangzhi county of Hunan Province. These large karst areas are a Paradise for cavers. Tunnel caves are neighbouring alpine shafts, big blue springs and deep sinkholes. We explored 50 caves and mapped 64 km of galleries. Five caves were longer than 5 km and another five deeper than 300 m. At 552 m, the Zhaidong is one of  China’s deepest. The counties of Xianfeng and Sangzhi are new regions for caving, but at Wufeng and Hefeng we continued explorations begun in 1989 (in the Changleping anticline and in the Yanziping Syncline). Except Sangzhi county the regions explored are mountainous and it is very exciting to use single rope techniques in Chinese size caves (that is to say climbing in the centre of 20 x 20 m shafts).

Keys-words : Wufeng, Hefeng, Sangzhi, Hubei, Hunan, Subtropical karst, Mountainous karst, China, Zhaidong, tunnel cave, sinkhole, shaft, resurgence, Changleping, Yanziping.