Llanelly (Welsh: Llanelli) is the name of both a parish and community in the principle area of Monmouthshire, within the historic boundaries of Brecknockshire, south-east Wales. It roughly covers the area of the Clydach Gorge. The population of both the civil parish and electoral ward at the 2011 census was 3,899.
The parish encompasses the area surrounding the Clydach Gorge, west of Abergavenny, east of Brynmawr and south of Crickhowell. The church [1] is dedicated to St Elli.
Llanelly Hill, Blackrock, Clydach, Maesygwartha and Gilwern are the main settlements in the parish. Llannelly Hill occupies the north-west hilltop of the Clydach Gorge. It developed as a result of coal mining and limestone quarrying for the nearby ironwworks including Clydach ironworks and Ebbw Vale ironworks.
Blackrock and Clydach North (also referred to as Cheltenham) both built up along the turnpike road that ran on the north side of the river between Govilon and Merthyr Tydfil. Clydach South developed on the south side of the river above the ironworks, climbing the north-west slopes towards Llanelly Hill.
Gilwern is located at the mouth of the River Clydach, where it meets the river Usk. Maesygwartha lies between Clydach and Gilwern along one of the many tram roads in the gorge.