The Slate Industry of North and Mid Wales

Penrhyn Quarry, Bethesda

The dominant force in the industry has always been Penrhyn Quarry at Bethesda.  Its only rival in terms of size or production was Dinorwic.  It was owned from the 1780's by the Pennant family and rapidly developed as a major industrial unit.  The majority of quarrying was still small scale at that time and was being carried on as an aside from farming.  The gallery system was introduced early on enabling large numbers of men to work on the same vein at different heights.  Over 20 galleries were ultimately in use each connected by incline to the dressing mills at lower levels.  Over a hundred thousand tons of year was a typical production level with over 2,000 employed.  It possessed its own external and internal tramway system from an early date and had its own port and ships.  The profits which flowed from the quarry enabled the Pennants  to construct Penrhyn Castle with its unique slate four poster bed.  Not all was plain sailing however as the haughty attitudes of the English owners went down poorly with the Welsh Quarrymen  and several long and acrimonious strikes took place.  Penrhyn was responsible for bringing in some standardisation into the industry most notably in its naming system for the size of roofing slates.  This was based improbably on female terms for the aristocracy and some of the terms: Duchess, Countess, Empress and Wide Ladies(!) etc. remain in use today - a full list may be found here.

The easily won slate at Penrhyn has enabled the quarry to weather the decline in the industry and it retains its premier position.  However continuing extraction of slate has resulted in the disappearance of almost all traces of Penrhyn's history.

 An interesting account of Michael Faraday's visit to Penrhyn in 1819 may be read here.
  There is also a page of archive black & white views of Penrhyn. which may be viewed here.

A History Of Bangor Blues In Ireland by Peter Lagan

Penrhyn Quarry and the Irish market by Peter Lagan

The extensive collection of modern day dressing sheds on Red Lion level.

Penrhyn in the snow

Penrhyn quarry in the snow with Bethesda in the foreground.  Some of the remaining galleries are in the centre of the photo.

Compared with the photo below, it shows how the old system of gallery working has now been hidden by waste rock tipped from the modern workings higher up.

Y Talcen Mawr

A view of Penrhyn quarry in the 1890's.  The huge pillar of rock in the centre was known as Y Talcen Mawr.  It weighed 125,000 tons and was demolished on the 27th of April 1895 by using 7 tons of explosives!  Many thanks to Peter Hodds for the details.

The Sebastopol water balance incline.

Preserved Water Balance at Penrhyn Quarry, Bethesda. The two moveable platforms of the incline had tanks for water beneath.  An empty wagon with a full tank of water would haul up a loaded wagon with its water tank empty. The raised tank on the right contained water which was used to supply the tanks under the platforms. Penrhyn at one time had eight of these balances and this one was named Sebastopol, as it was built during the Crimean War.  Another water balance - Princess May - also remains at the quarry.

Photographs obtained with the permission of Alfred Macalpine Slate Ltd.

Port Penrhyn near Bangor, Gwynedd.

Port Penrhyn
            near Bangor, gwynedd.

Port Penrhyn on the Menai Straits was built over 200 years ago by the owners of Penrhyn Quarry.  It was linked to the quarry by a horse drawn tramway from the start and by a steam operated line on an improved alignment from 1878.   This closed in 1962 but two of the locos, Blanche and Linda, now work on the Ffestiniog Railway.
The port also had a main line connection to the Chester and Holyhead Railway from 1852.  Now used by fishing and pleasure boats its heritage is clear from the slate slabs used to edge the quays.  There are still a number of the original buildings on site including the locomotive shed and a circular toilet!  Nearby, one of the incline drum houses on the original horse tramway route has been converted into a house.


The splendid circular toilet at Port Penrhyn, this is now a listed building.

Blanche of the Ffestiniog Railway.  This locomotive worked between the quarry and Port Penrhyn until 1962.

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