Deepest underwater caves
Ranked by reported survey data.
| # | Cave | Location | Max depth | Source |
|---|---|---|---|---|
| 1 | Gouffre du Petit Saint Cassien | Alpes-Côte d'Azur, France | 403 m | Cave-Exploring World Long Caves Tertiary / aggregate source Provided by: Liste des cavites naturelles les plus longues de France |
| 2 | Rèseau Lot du Bois - Source du pissieux | Auvergne-Rhone-Alpes, France | 185 m | Cave-Exploring World Long Caves Tertiary / aggregate source Provided by: Liste des cavites naturelles les plus longues de France |
| 3 | Fuente Azul | Hortigüela - Burgos, Castilla León, Spain | 135 m | Grandes Cavidades Submarinas de España Tertiary / aggregate source Provided by: Espeleobuceo en Burgos 2008 ( R. García) |
| 4 | Cathedral-Falmouth System | Suwannee, Florida, USA | 130.8 m | Cave-Exploring World Long Caves Secondary source Provided by: Andrew Pitkin e-mail |
| 5 | Pozo Azul | Covanera, Burgos, Spain | 126 m | Cave-Exploring World Long Caves Secondary source Provided by: Jose Luis Membrado e-mail |
| 6 | Weeki Wachee Spring | Hernando, Florida, USA | 124.1 m | Cave-Exploring World Long Caves Secondary source Provided by: Andrew Pitkin e-mail |
| 7 | Sistema Sac Actun | Quintana Roo, Mexico | 119.2 m | QRSS Long Underwater Caves Secondary source Provided by: Alvarez/Nava/Reato/Picard |
| 8 | Wakulla Cave System | Leon/Wakulla, Florida, USA | 106.7 m | Cave-Exploring World Long Caves Secondary source Provided by: Casey McKinlay e-mail |
| 9 | Cenote Godzilla | Quintana Roo, Mexico | 97.1 m | QRSS Long Underwater Caves PDF Secondary source Provided by: Ternat, Coffield-Feith, Bulman, Widmann |
| 10 | Uelh de Sescorjada | Vielha e Mijaran - Lleida, Catalunya, Spain | 95 m | Grandes Cavidades Submarinas de España Tertiary / aggregate source Provided by: FEDERACIÓ CATALANA ESPELEOLOGIA |