northcave
September 7th, 2008, 22:04
Background:
Croesor and Rhosydd are two very large slate mines located deep within the dome-shaped mountain of Moelwyn Mawr, North Wales. Whilst both mines are extensive, Rhosydd is the larger of the two with no less than 170 chambers arranged over 14 floors.
Both quarries ceased slate production in the 1930s, after around 100 years of effort. Between them they employed around 500 men at their peak, producing in excess of 11,000 tons of finished slates annually.
Both mines have seen serious collapses in their time. In 1900 a large section of Rhosydd caved in burying rockmen and creating a massive crater on the surface. Rhosydd has suffered another large collapse in the late 1990s which has destroyed, amongst other things, the main underground incline. The whole mine is largely shattered and not in particularly good condition.
Both mines are also deeply flooded. More than a third of Rhosydd is below the water level, and more than half of Croesor has been lost in the same way.
Miraculously, despite the numerous collapses and rock falls in both mines, it is still just about possible to enter one mine, go right to the other end, pass through into the other mine and exit, which these set of photos illustrate. The journey is appropriately known as the Croesor-Rhosydd Through Trip, and remains one of the classic adventures for the underground explorer.
Explore & Advice:
Parties present: Userscott, Stepping Lightly, Snappel
Please note that if you plan to do this trip research it thoroughly first, gain all the necessary experience and go with someone who is versed in caving or mining already. Many people have had to be rescued from this mine and there are numerous situations that could lead to a serious injury / death if not undertaken properly.
Thanks to Userscott for providing caving suits, haul bags and cave experience. Thanks to Stepping Lightly for charging ahead and being the test dummy for the bridges and zip lines. A real life saver. No thanks for lumping me with the crappy pully. Note the images of the other whizzing across the gaps in record speed whilst I would get about 6 yards and promptly stop, hanging above either a void of darkness or a pool of ice cold water, 100 ft deep. Gulp.
The bridges you see are literally hanging from 120 year old rusted bolts in the roof. God knows how they are still there. Regardless walking across them is somewhat un-nerving. In many of the huge chambers lay fresh house sized boulders. Complete silence in these areas was a must to avoid the chance of being quickly turned into spam. Recently a group was rumoured to have been disabled after a huge boulder came off the roof and land next to them. Although no one was hit, the shock wave apparently disabled them where they stood and awaited rescue (sourced info).
I'll stop rambling now and point you to this PDF (http://www.mine-explorer.co.uk/mines/Croesor_195/Croesor_3308.pdf) which gives an excellent account of the through trip.
http://northcave.net/gallery/underground/Croesor%20Mines/Large/a.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/b.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/c.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/d.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/e.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/g.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/h.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/i.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/j.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/l.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/n.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/o.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/r.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/s.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/t.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/u.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/v.jpg
Croesor and Rhosydd are two very large slate mines located deep within the dome-shaped mountain of Moelwyn Mawr, North Wales. Whilst both mines are extensive, Rhosydd is the larger of the two with no less than 170 chambers arranged over 14 floors.
Both quarries ceased slate production in the 1930s, after around 100 years of effort. Between them they employed around 500 men at their peak, producing in excess of 11,000 tons of finished slates annually.
Both mines have seen serious collapses in their time. In 1900 a large section of Rhosydd caved in burying rockmen and creating a massive crater on the surface. Rhosydd has suffered another large collapse in the late 1990s which has destroyed, amongst other things, the main underground incline. The whole mine is largely shattered and not in particularly good condition.
Both mines are also deeply flooded. More than a third of Rhosydd is below the water level, and more than half of Croesor has been lost in the same way.
Miraculously, despite the numerous collapses and rock falls in both mines, it is still just about possible to enter one mine, go right to the other end, pass through into the other mine and exit, which these set of photos illustrate. The journey is appropriately known as the Croesor-Rhosydd Through Trip, and remains one of the classic adventures for the underground explorer.
Explore & Advice:
Parties present: Userscott, Stepping Lightly, Snappel
Please note that if you plan to do this trip research it thoroughly first, gain all the necessary experience and go with someone who is versed in caving or mining already. Many people have had to be rescued from this mine and there are numerous situations that could lead to a serious injury / death if not undertaken properly.
Thanks to Userscott for providing caving suits, haul bags and cave experience. Thanks to Stepping Lightly for charging ahead and being the test dummy for the bridges and zip lines. A real life saver. No thanks for lumping me with the crappy pully. Note the images of the other whizzing across the gaps in record speed whilst I would get about 6 yards and promptly stop, hanging above either a void of darkness or a pool of ice cold water, 100 ft deep. Gulp.
The bridges you see are literally hanging from 120 year old rusted bolts in the roof. God knows how they are still there. Regardless walking across them is somewhat un-nerving. In many of the huge chambers lay fresh house sized boulders. Complete silence in these areas was a must to avoid the chance of being quickly turned into spam. Recently a group was rumoured to have been disabled after a huge boulder came off the roof and land next to them. Although no one was hit, the shock wave apparently disabled them where they stood and awaited rescue (sourced info).
I'll stop rambling now and point you to this PDF (http://www.mine-explorer.co.uk/mines/Croesor_195/Croesor_3308.pdf) which gives an excellent account of the through trip.
http://northcave.net/gallery/underground/Croesor%20Mines/Large/a.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/b.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/c.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/d.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/e.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/g.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/h.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/i.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/j.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/l.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/n.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/o.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/r.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/s.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/t.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/u.jpg
http://northcave.net/gallery/underground/Croesor%20Mines/Large/v.jpg