Map of the Cwmorthin Workings
A coloured composite plan of Cwmorthin is available for download below as a PDF file:
cwmorthin_plan.pdf (577kb)
Having been drawn from numerous original mine plans, it should be considered as a general guide rather than very specific on detail. Most of the adits on the plan are no longer open - the two that are are the Back Vein's "1 North", more commonly referred to as Lake Level, and the Old Vein's "2 South", more commonly referred to as the Smoke Flue.
Floors going upwards from Lake Level are numbered sequentially, Floor 1 being Lake Level, going up to ultimately to floor 8. Floors going downwards from Lake Level are lettered, Floor A being the first one down, then B, C, D, and finally E. There is an F floor and a G floor in Oakeley, but floors deeper than these are all under water now (they actually go down as far as S floor!). Almost all workings above Lake Level (Floor 1) are inaccessible now.
Cwmorthin mainly worked two slate veins - the Back Vein and the Old Vein. These can almost be considered separate mines, just interconnected in several places. Several smaller veins were also worked on a very limited scale (such as the Stripy Vein, which sits between the Back Vein and the Old Vein).
The areas in Blue on the map show the Old Vein workings. Most Old Vein workings from Lake Level down to E floor are accessible by one means or another but most of this ground is fractured and in generally poor condition. The areas in Orange show the Back Vein Workings from Lake Level and below. There are also upper floors in the back vein right up to floor 8 - but they are omitted from the map for clarity and like the upper Old Vein floors, are largely inaccessible now. Almost all of the lower Back Vein workings are accessible and are in a good condition, with the exception of some localised damage from Pillar Robbing.
The areas in Green represent the only small areas of the neighbouring Oakeley Mine to which access is permitted. Please do not stray beyond the map into deeper parts of Oakeley as there is no access agreement or permission in place for us to do so.
Photos of the Cwmorthin Workings
Coming soon!