Ogof Ffynnon Ddu
Ogof Ffynnon Ddu (Welsh for cave of the black spring), also known informally as OFD, is a cave under a hillside in the area surrounding Penwyllt in the Upper Swansea Valley in South Wales. It is the second longest cave in Wales and the deepest in the United Kingdom.
Details
- Depth
- 274.5 m
- Access
- South Wales Caving Club—see [http://www.swcc.org.uk/joomla-swcc/ website] for details
- Length
- 59 km
- Survey
- [http://www.clipstone1.plus.com/survey1.htm South Wales Caving Club 2014]
- Geology
- Limestone
- Language
- Welsh
- Location
- Upper Swansea Valley
- Discovery
- South Wales Caving Club 1946
- Translation
- Cave of the black spring
- Entrance Count
- 3