| cave: cueva pothole: sima gallery: galeria | stalactite/stalagmite: caving: caver: |
The largest cave chamber in Europe is the Torca del Carlista in the Basque Country. It measures some 520 metres by 245m. It is the fourth (not the second as some sources claim!) largest cave chamber in the world. Legend has it that a Carlist follower threw himself to his death here rather than be taken alive.
Longest caves in Spain
| Ojo Guareña | Burgos | 110,000 m |
| Sistema del Alto Tejuelo | Cantabria | 77,610 m |
| Sistema del Gándara | Cantabria | 74,300 m |
| Sistema del Gándara | Cantabria | 74.300 m |
| Cueva del Valle (Red del Silencio) | Cantabria/Vizcaya | 60.223 m |
Deepest caves in Spain
| Torca del Cerro del Cuevón | Asturias | -1589 m |
| Sistema del Trave | Asturias | -1441 m |
| Ilaminako Ateeneko Leizea | Navarra/Huesca | -1408 m |
| Sistema Arañonera | Huesca | ±1349 m |
| Sistema de la Piedra de San Martín | Navarra/Francia | -1342 m |
| Sima de la Cornisa-Torca Magali | León | -1330 m |