Deepest caves
| Rank | Cave Name | Length (km) | Vertical Range (m) | Region | Type | More Info |
|---|---|---|---|---|---|---|
| 1 | Ogof Ffynnon Ddu | 60.644 | 309.5 | South Wales | All cave | Short description |
| 2 | Ogof Daren Cilau System | 28 | 232 | South Wales | All cave | Short description |
| 3 | Agen Allwedd | 32.8 | 160 | South Wales | All cave | Short description |
| 4 | Ogof Draenen | 70 | 151 | South Wales | All cave | Short description |
| 5 | Dan-Yr-Ogof | 16 | 150 | South Wales | All cave | Short description |
| 6 | Tunnel Cave | 2.135 | 145 | South Wales | All cave | Short description |
| 7 | Little Neath River Cave | 8.8 | 125 | South Wales | All cave | Short description |
| 8 | Ogof Craig A Ffynnon | 8 | 115 | South Wales | All cave | Short description |
| 9 | Ogof Llyn Parc | 4 | 110 | North Wales | Part mine | Short description |
| 10 | Milwr Tunnel - Powell's Lode Cavern | < 1 | 110 | North Wales | Part mine | Short description |
| 11 | Ogof Hesp Alyn | 2 | 97 | North Wales | All cave | Short description |
| 12 | Pant Mawr Pot | 1.2 | 97 | South Wales | All cave | Short description |
| 13 | Pwll Dwfn | < 1 | 97 | South Wales | All cave | Short description |
| 14 | Ogof Ap Robert | 1.015 | 90 | South Wales | All cave | Short description |
| 15 | Crescent Cave | < 1 | 81 | South Wales | All cave | Short description |
| 16 | Llanelly Quarry Pot | 1.705 | 80 | South Wales | All cave | Short description |
| 17 | Ogof Fawr | 1.1 | 76 | South Wales | All cave | Short description |
| 18 | Ogof Pwll Swnd | 1.075 | 76 | South Wales | All cave | |
| 19 | Blaen Onneu Quarry Pot | < 1 | 74 | South Wales | All cave | |
| 20 | Carno | 8.9 | 63 | South Wales | All cave | Short description |
If you don't see the cave you want, but you know it should be in the Wales section, remember that this list only shows caves with at least 60 m depth of natural passage. Other caves may show up in the list of longest caves in Wales.
However, if you are looking for a specific cave that does have at least 60 m depth of natural passage, and should be listed here, please let me know about it so I can update the database.