The Beginnings of the Slate Industry

The exact origin's of the industry are unknown, although it is suggested that slate quarrying in Pembrokeshire may date back to Roman times. This theory is based on the evidence mainly of slate fragments found in Roman quays at Caerleon in Monmouthshire, which were identified as waste from slate making and with their origin in the Preseli Hills.

In medieval times, slate became more widespread, although is was probably not used intensively. However, the main sources were apparently quarries in Devon and Cornwall and there is little evidence of the use of slate from South West Wales. One likely case where Pembrokeshire slate was used was the probably-late-medieval roof of St. Barruch's chapel on Barry Island.

In the 16th and 17th centuries small quantities of slate were exported from Pembrokeshire, e.g. 11,000 slate stones (perhaps 3 tons) to Bristol in 1566,  40M [see below for explanation] of slates (perhaps 10 tons) to Ireland in 1616, and 36 thousand of hillinge stones (say 9 tons) from Fishguard to Ireland in 1639.

It was in 1603 that George Owen showed that there was then well-established and extensive slate quarrying in at least that part of Pembrokeshire around Newport and Nevern, and it is probably significant that the cargo of 1566 mentioned above was sent by a Nevern merchant in a Newport ship.

It is not until the later part of the 18th Century that there is firm evidence to show that slate production was taking place in Pembrokeshire. At this time there were established quarries at Cilgerran and Glogue in the North East of the county. It was not long after that other quarries began to pop up around the county.