top of page
Charles Hipkin Craig y Llyn

Inland Rock and Cliff

Exposed crags, scree

The State of Nature in Inland Rock and Cliff in Neath Port Talbot

The extent and connectivity of Inland Rock and Cliff in NPT has hardly changed for hundreds of years. However, there has been some deterioration in the condition of Craig y Llyn in recent decades. Invasion of scree and cliff by Sitka Spruce regenerating from seed that has rained in from surrounding plantations has become a significant problem and traffic pollution originating from the nearby Rhigos Mountain Road may also be a problem. The construction of a zipline above nearby Llyn Fawr is a reminder that many upland cliff habitats in South Wales are under pressure from tourist developments.

Overall, we have assessed the resilience and state of nature in Inland Rock and Cliff in Neath Port Talbot as fair.


The north-facing sandstone cliffs of Craig y Llyn above Llyn Fach are the most important example of this type of habitat in Glamorgan and although this habitat only supports a small proportion of NPT’s priority species, there is a community of northern boreal and arctic-montane plants here which has a unique place in the county. For example, species such as Cowberry, Crowberry, Lesser Meadow-rue, Stone Bramble, Fir Clubmoss, Wilson’s Filmy-fern, Oak Fern, Brittle Bladder-fern, Beech Fern, Parsley Fern, Mountain Male-fern, Black Rock-moss and Stiff Apple-moss are either only found here or are very uncommon elsewhere in NPT.


Smaller north-facing outcrops such as those at Craig y Pant in the Neath Valley and above Cymmer in the upper Afan Valley also support interesting bryophyte assemblages with Hill Notchwort, Trunk Paw-wort and Neat Silk-moss and the only occurrence of Lanceolate Spleenwort in NPT.


In the past these habitats have provided breeding grounds for Kestrel, Peregrine Falcon, Whinchat and Ring Ouzel, although the latter has not bred in the county for over 50 years.

Upland rock and cliff NPT LNP Nature
Charles Hipkin Craig y Llyn

Actions for the recovery of
Inland Rock and Cliff habitats in NPT

Responsibility for these actions lie with all of us and as such, we have not sought to assign actions to particular organisations or groups. Instead, it is our hope that this document will provide the guidance and inspiration for anybody, or any group or organisation, to undertake the actions that are within their capability to deliver. The Secretariat of NPT LNP (NPT Council) are providing a facilitation role to support, collate and monitor work towards these actions. If you would like to discuss your potential involvement in delivery of these actions, please get in touch with

Tonbridge Filmy Fern © Richard Pryce NPT Nature

©Richard Pryce

Kestrel Vaughn Matthews Neath Port Talbot Nature

©Vaughn Matthews

Huperzia selago fir clubmoss Cwm Saerbren Neath Port Talbot NPT Nature


The crags of Craig y Llyn are home to a number of fern species that are scarce or rare in south Wales and of conservation concern. One of them is Wilson’s Filmy-fern, a small plant with thin, translucent fronds that form a mat on shady, vertical rocks. This Atlantic species is confined to humid ravines and north-facing cliffs in south Wales and is only known from Craig y Llyn in NPT. That is also true of Mountain Male-fern, a northern montane species at the southern limit of its British range in Glamorgan. Other ferns worthy of note here are Oak Fern and Beech Fern. These two Boreo-temperate species make attractive displays in the hardy plant communities of Craig y Llyn and have few other locations in the county.


The Kestrel is now Red Listed in Wales following a widespread decline across the country. The reasons for this decline are thought to be related to increased mortality with juvenile birds unable to find sufficient insect food, predation by Goshawks and also poisoning by rodenticides. The Kestrel was once a fairly common breeding resident in NPT, its main habitat being rough grassland, where it preys on voles, and also coastal areas. For many years they bred in the roof of the Fords factory near Jersey Marine (now Bay Studios) and on some inland cliffs but the species has declined dramatically in recent years with few breeding records.


NPT has 3 species of clubmosses; Alpine, Fir and Stag‘s-horn. They are integral and iconic features of the county’s upland biodiversity. Contrary to their misleading name, they are not mosses at all but vascular plants which are related closely to ferns. In the past, when the high ground of NPT was dominated by moderately-grazed, unimproved moorland and dwarf-shrub heath, Fir and Stag’s-horn Clubmoss species would have been relatively widespread. Today, they are uncommon in the intensively grazed uplands of NPT. Fir Clubmoss is only found on north-facing sandstone ledges and scree and in banks of un-grazed dwarf-shrub heath in conifer plantations. Alpine and Stag’s-horn Clubmoss are confined to these banks of heather and bilberry in plantations. Alpine Clubmoss, which is our rarest clubmoss, occurs at its UK southern limit in NPT. All our clubmoss species are vulnerable and endangered.



Craig y Llyn SSSI consists of two north-east-facing hollows that were cut by Pleistocene ice or snow into the edge of the Pennant Sandstone Plateau and also includes the lake below, Llyn Fach. Here, the high cliffs, ravines and flushes support many montane species such as Wilson's Filmy Fern, Fir Clubmoss, Oak-fern, Mountain Male-fern and a number of upland bryophytes which are otherwise uncommon in south Wales. Llyn Fach has a suite of uncommon aquatic species that are associated with upland oligotrophic lakes such as Water Lobelia, Quillwort and Floating Bur-reed. Many of these species are near or at their southern distribution limit in Britain in this site. Analysis of the pollen preserved in Ffos Cenglau has yielded data on the post-glacial sequence of woodland types in South Wales.


Llyn Fach and its surrounds are managed by the Wildlife Trust of South and West Wales (WTSWW) who organise surveys and monitoring of the lake and grassland habitats which inform management decisions. For example, survey rafts are used to monitor the population of Water Vole that has recently been discovered here and occasional, humane trapping is carried out to remove predatory American Mink. Other management practices include the introduction of cattle in summer for conservation grazing, scrub clearance and the removal of encroaching conifers (mostly Sitka Spruce) which are regenerating onsite. WTSWW is also working towards increasing the public understanding of the importance of the species at this reserve and reducing anti-social behaviour.

Volunteers working at WTSWW Llyn Fach NPT Nature
bottom of page