Bwlch y Plwm Mine

Location
SH 624 412

Directions
Close to Garreg, Near Porthmadog. It is marked on the O/S maps as “tips”. Just above this it is marked again as “tips” but it also carries the name “Bwlch y Plwm” – you need the lower one (southern).
On the country lane immediately south (by yards) of the “tips” is a farm and a farm gate across the road. Pass through this (it’s a public road) and park up immediately next to a ruined outbuilding.
The lowest entrance (drainage adit) is 30 yards away and goes UNDERNEATH the road. The other entrances are all above following the reasonably obvious vein up the mountain. The very top workings are the second “tips” on the O/S map.

Access
Unknown. Ungated.

Suggested Equipment
None for drainage adit. SRT for Level 2, none for other higher adits.

Length
In excess of 2 kilometres of passage ways

Flood Risk
Level 2 adit clearly floods to the ceiling but work has been carried out to keep the water low. However, it will clearly flood again to the roof. Level 3 adit is already flooded to the ceiling. The levels above appear to be unlikely to flood. The main drainage adit has also been worked on to ensure it doesn’t flood and is unlikely too.

Mine Attributes
Lead

Description
A surprisingly large mine carved into the mountainside and covered with trees (the mountain, not the mine).

From the bottom drainage adit ,there are numerous adits as you work your way up the mountainside all of which are reasonably easy to find by following the topography.

The topmost workings are essentially an interesting large cavern with a level just below which yields some very nice mineral formations.

The Level 2 will get you wet up to your waist and probably higher as water is actively running IN and the adit is trying to sump. However, once in it becomes dry with various passages running around leading to an internal open workings where the floor gives way. A traverse line exists here to continue along level 2 and also rigging down to level 1.

The main drainage adit is 700m in length although this only accounts for a straight run. There is a worked chamber inside with other passages leading off, some of which are, themselves several hundred metres long with areas to climb up to higher levels.

Unexplored Passages
Plenty ~ including level 2 adit beyond the traverse, level 3 adit (flooded), level 4 adit (drop into entrance which I couldn’t manage) and a higher passage in level 6 I could not reach.

None of the upward passages from level one were explored and neither was a level passage that utilised a short traverse.

Digs
None Known but work appears to be on-going in rigging the mine.

Links
http://www.mine-explorer.co.uk/mines/Bwlych-y-Plwm_1044/Bwlych-y-Plwm.asp

http://www.aditnow.co.uk/mines/Bwlch-y-Plwm-Lead-Mine/

http://www.geograph.org.uk/photo/619700