Cwm Colhuw – Llantwit Major

Grid References O.S. Explorer map 151. Main entrance: SS960674

Cwm Colhuw by Vaughn Matthews

Cwm Colhuw by Vaughn Matthews

Status The site is partly designated a Scheduled Ancient Monument and lies within the Glamorgan Heritage Coast.

Tenure Held since February 1989 on a 99 year lease from the Vale of Glamorgan Council.

Size 11.5 ha (28.4 acres).

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Location and Access Notes

1 km southwest of Llantwit Major, situated on the southeast side of the beach road. Access on foot either from a stile at the head of the valley (SS968678) or by way of the steps from the eastern side of the beach car park. A public footpath runs the length of the reserve, and the Heritage Coast footpath crosses the site, on the cliff top. Not accessible to wheelchairs.

Public transport

Trains from Bridgend and bus services 142 from Bridgend, X44 and X2 from Cardiff to Llantwit Major, then walk towards the beach.

Description: Coastal calcareous grassland, Ash woodland and scrub.

Yellowhammer in Gorse by Harry Hogg

Yellowhammer in Gorse by Harry Hogg

The reserve is situated on the southern slope of the Afon Colhuw. A postcard of the Colhuw valley taken in the 1930s shows the reserve as open grazed pasture with isolated scrub. Grazing ceased during the Second World War, when the site was used for allotments in the “Dig for Victory” campaign, and then Hawthorn, Blackthorn, Gorse and Bramble colonised the majority of the slope with secondary Ash woodland taking over at the inland end.

The scrub and hedgerows provide nesting habitat for a number of birds such as Bullfinch, Goldfinch, Grasshopper Warbler, Linnet and Yellowhammer, and also summer migrants such as Willow Warbler and Whitethroat. Kestrel breed on the adjacent cliffs and use the grassland for hunting, and Peregrine is regularly seen.

Two calcareous grassland fields on the summit of the slope are dominated by Oat Grass and Yorkshire Fog, with clumps of Cocksfoot, Bird’s-foot Trefoil (6-9), Salad Burnet (5-8), Kidney Vetch (6-9), and Wild Thyme (5-7) in the shorter Rabbit grazed turf, on the ant hills, and archaeological remains. Nationally scarce Wild Cabbage grows near the cliff edge, in places sheltered from grazing. The grassland provides a habitat for butterflies such as Common Blue (4-9), Meadow Brown (6-9), Small Heath (5-9), Ringlet (6-7) and Small Blue (5-6 + 8).

The reserve contains part of the boundary bank and ditches of an Iron Age Promontory Fort. The majority of the Fort including the impressive ramparts, known locally as “Castle Ditches”, are just outside the reserve boundary to the east.

Cwm Colhuw