The 1st edition 25-inch Ordnance Survey map published in 1889 depicts and annotates a lime kiln at Pensarn Wharf on the northeast bank of the river Artro. This formed part of a complex of buildings on the quayside, which had developed by the 2nd edition map of 1901 and included a stable, grain store and office (Davidson et al. 2007). At this date the lime kiln also appears to have still been in use. The kiln is also depicted on the 1840 tithe map for the parish of Llanfair, though no additional quayside buildings are shown, despite other archive records suggest some form of quay is likely (Davidson et al. 2007)

The kiln survives today having been consolidated and incorporated into a late 20th century building. The wharf is now used as an outdoor activities centre for CMC Adventure. On a visit by RCAHMW in August 2024 the centre was closed and awaiting a new phase of redevelopment to begin.

The lime kiln is a substantial structure, square in shape and built of roughly dressed stone blocks.  Externally the southwest face of the kiln remains visible and is 6.9 metres wide and over 4 metres high. Set within the centre of this face is a kiln eye 2 metres wide and 2.1 metres high, defined by a rounded arch of dressed voussoir stones. The kiln eye is 1.8 metres deep, the side walls and roof sloping inwards and downwards the rear of the chamber. Here brickwork defines the draw hole of the kiln a 0.73 metre wide and 0.3 metre high opening supported by an iron bar.

Contextual Information  

Lime kilns are a characteristic feature along the coastlines of Wales. They are predominantly of 19th century date, although some were built prior to that, and some continued in use into the 20th century. They were used for burning limestone to make lime for use in agriculture and building. The former through spreading on the fields as a fertiliser and to counteract soil acidity, and the latter to make lime mortar. Their coastal position related to the need in many places to import the limestone for burning, and the culm (coal) that was used for fuel. Proximity to the shoreline reduced the need to move the limestone and coal very far after unloading. 

Coastal lime kilns are generally round or square in shape and normally slightly wider than they are tall. They have a conical opening in their top, called a crucible, into which the limestone and culm was layered. Openings on either side, called the kiln eyes, connected to the base of the crucible and served for lighting the kiln and to allow air to be drawn into the crucible. After burning, the lime could be raked out via the kiln eyes. The kiln eyes come in many different shapes and sizes, from arched, to flat-topped, to tall and narrow. 

Lime kilns were often constructed in pairs, with a small rectangular cottage for the kiln keepers in between them. At smaller landing places only a single kiln might have been built. In nearly all cases some sort of ramp was needed to carry the limestone and coal to a point where it could be added into the crucible from above. Many lime kilns are found built against the valley sides within coves or harbours, allowing the access ramp to be cut from the adjacent bank side, rather than needing to be built. 

Louise Barker, RCAHMW, 20 August 2024.

Sources

Davidson, A., Gwyn, D. & Roberts, J. , 2007 , Ports and Harbours of Gwynedd: Pensarn (Gwynedd Archaeological Trust Report: https://www.walesher1974.org/her/groups/GAT/media/GAT_Reports/GATreport_671.3_compressed.pdf )

National Library Wales: 1840 Tithe map and apportionment for the parish of Llanfair in Merionethshire https://places.library.wales/home

OS 1st Edition 25-inch map (published 1889): Merionethshire XXV sheet 8.

OS 2nd Edition 25-inch map (published 1901): Merionethshire XXV sheet 8.