Defynnog

Defynnog, also known as Devynock in some historical documents, is a small village in the community of Maescar in the historic county of Breconshire (Brecknockshire), now lying within the county of Powys, Wales. It lies immediately south of Sennybridge and about ten miles west of Brecon within the Brecon Beacons National Park.

An important place in the past, Defynnog lost much of its importance as Sennybridge became more developed. The village (which has also been referred to historically as 'Devynnock') is located in the Brecon Beacons National Park one mile south of Sennybridge, beside the Afon Senni just south of its confluence with the River Usk and where the A4215 road meets the A4065. The Welsh name signifies the 'territory belonging to Dyfwn'.

To the southwest of the village is "Y Gaer", a small oval hillfort with a sub-rectangular annex standing on a ridge. The ramparts and ditches are covered with bracken.

The local church, dedicated to Saint Cynog, contains an ancient stone with Ogham inscriptions and is a grade I listed building. In 1836 a chapel in the parish of Defynnog was dedicated to Saint Callwen.

In 2014, a Yew (Taxus baccata) found in the churchyard was estimated to be five thousand plus years old. It has been subject to extensive investigation, including dendrochronology, and DNA analysis. The crown of the tree is 60 ft in diameter.

The rectory within the Church grounds was once the property of Moses Williams FRS and his inscription is to found on the beams of one of the attics. The property immediately south of the lychgate (Ty Defynnog, Defynnog House) may have been made up of two former cottages. Its cellar contains a stone slab of uncertain purpose. It is a Grade II listed building

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