Dyffryn Ardudwy and Coed Ystumgwern are adjoining ribbon settlements, with Dyffryn Ardudwy forming the southerly half of the settlement, and Coed Ystumgwern forming the north. They are situated approximately 13km (8 miles) south of Harlech. According to Gwynedd Archaeological Trust, ‘Ystumgwern was the commotal centre of Ardudwy uwch Artro in the medieval period, although the exact location of the llys is not known,’ although the farm which retains the name ‘Ystumgwern’ is situated a little to the north west of Coed Ystumgwern.

‘As with all the nucleated settlements in Ardudwy, this settlement really developed in the 19th century along the line of the improved road (the railway lies some distance away to the west), with early cores of buildings loosely centred around the two churches, although earlier concentrations of buildings exist in small clusters just below the main road. Unlike Llanbedr and Tal-y-Bont, both of which grew from strategic road/river crossings, however, there appears to be no apparent reason for the development of Dyffryn Ardudwy (there is no substantial coaching inn, for example).

The six inch Ordnance Survey map published in 1888 shows that there was a smithy and a Congregational Chapel (NPRN 8464) in Coed Ystumgwern, whilst Dyffryn Ardudwy also had a smithy, a corn mill (called the King’s Mill – NPRN 40018), a school, a Calvinistic Methodist Chapel (NPRN 8467), a Wesleyan Methodist Chapel (NPRN 8470), and a public house called the Kings Head Inn. By the time the second edition of the six inch Ordnance Survey map was published in 1901, there was a post office and a Baptist Chapel (NPRN 8465) in Dyffryn Ardudwy.  The six inch Ordnance Map published in 1953 showed that the smithy in Dyffryn Ardudwy had gone, although the one at Coed Ystumgwern remained. The school had moved from near the centre of the settlement to an area a little to the south of Dyffryn Ardudwy. All four chapels remained open, as did the post office, although there is no mention of the Kings Head Inn. There were also two halls near the centre of the settlement.

Gwynedd Archaeological Trust notes that ‘Dyffryn Ardudwy has seen more expansion in the 20th century, with housing estates built at the south end of the village around the school in the 1930s, and up the hill slope behind in the 1960s. it has a series of commercial buildings which provide local services.’ Today, Ysgol Dyffryn Ardudwy primary school educated around 60 pupils through the medium of Welsh. Amenities in the village include a garage, a petrol station, a small convenience store, a post office and a café.

Sources: Historic Ordnance Survey maps; google maps; Gwynedd Archaeological Trust’s Historic Landscape Characterisation for Dyffryn Ardudwy and Coed Ystumgwern; Estyn report on Ysgol Dyffryn Ardudwy, published in September 2014

M. Ryder, RCAHMW, 14th December 2020