| Réseau Félix Trombe | |
| Map: | France |
| Relief: | yes |
| Coords: | 42.9666°N 0.8584°W |
| Location: | Arbas, France |
| Depth: | 1001 m |
| Length: | 117263 m |
| Discovery: | 1908 |
| Geology: | limestone |
| Elevation: | 1476 m |
| Entrance Count: | 59 |
The réseau Félix-Trombe or Coume Ouarnède is an underground karst network formed by a succession of wells and galleries dug into the limestone.
It is a mythical network for speleologists from all over the world. It takes its name from a famous French speleologist: Félix Trombe.
The réseau Félix-Trombe is located on the Arbas massif in the Pyrénées, south of the département in the région Occitanie.
The Félix-Trombe network is the longest underground network in France with 117 kilometres of galleries and 59 entrances. It is a complex cavity due to its significant overall difference in altitude (1,001 metres) and its numerous entrances.
The main cavities that make up this network are:[1] :
Also included are: :
On 15 and 16 September 2001 in 22 hours, about twenty cavers travelled the entire network from the former highest point (the Gouffre de la Coquille) to the lowest point of the network (the Goueil di Her).[2]