W02: Llangloffan Fen

Grid Reference: SM904319
SatNav Co-ordinates: N 51.94607°, W 05.05035°
Nearest postcode SA62 5ET


Llangloffan Fen is one of the largest surviving valley mires in Wales. The site covers nearly 40 hectares and is a classic river mire sitting on a wide flood plain. Glacial deposits may be present having diverted the river’s previous course to the west rather than its present course south towards Milford Haven. The source of the Western Cleddau river is nearby at Croesgoch, and the river flow grows with the confluence of drainage creeks in the Fen; it is hard to believe at this point that this small stream will become the large river that discharges over the weir at Haverfordwest.

Llangloffan Fen is a rare habitat and contains a number of species that are only found on this site in Pembrokeshire. The important ecologies are tall-fen communities, wet woodland with lichen, and grazed marshy grassland. The wetland acts as a buffering reservoir for the river flow, helping to moderate rapid increases and decreases in river flow during extreme weather events. The Fen and wet woodland are managed jointly by NRW at this site and the Wildlife Trust of South and West Wales (WTSWW) at a second site to the west.



Located part-way between the villages of Llangloffan and Castlemorris, the NRW site is next to the ancient road bridge over the river. A second car park and access point to the section of the Fen is located further along the B4331 Mathry road beyond Castlemorris village.



Boardwalks allow people to visit the tall fen communities throughout the reserve, but take care in places where the boardwalk is undergoing planned maintenance.



Car parking is available for several cars at the lay-by beyond the bridge at Llangloffan.



There are no facilities at the site. There are toilets, shops and a café in nearby Letterston.


Activities and Places of Interest nearby

Below the bridge is a handrail and steps to the river’s edge, which used to be a baptistry. However, these days the sewage outfall pipe opposite the steps precludes any entry to the water! Click to learn about how to protect inland waterways from sewage pollution.

A short drive towards Mathry is the second access point to Llangloffan Fen site managed by the Wildlife Trust of South and West Wales. Here visitors can walk across a grazed field to another area of boardwalk area within the tall-fen community. The boardwalk leads to a bird hide and further on to bridges over the Western Cleddau river, where quiet observation will reward with a host of different birdlife and mammals, including water voles, otters and badgers.

The Priskilly Forest Country House & Golf Course is nearby.


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The Cleddau Trail Map

The Pembrokeshire Rivers Trust Cleddau Trail takes you on two 'Source to Sea' river journeys. Follow the Western Cleddau Trail to discover unspoilt natural habitats, home to migratory salmon and sewin, kingfishers and other wildlife. The Eastern Cleddau Trail follows the flow of Pembrokeshire's rainwater as it becomes drinking water.


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