Llandecwyn () is a hamlet near Penrhyndeudraeth in Gwynedd, Wales.
The bulk of the population (between 40 and 50 houses) is now located around Cilfor close to the A496 road and served by Llandecwyn railway station, with a cluster of under ten houses around the road junction at Capel Brontecwyn half a mile up the hill to the southeast, and other isolated houses and farms scattered across the hillsides. Formerly, there was a sizeable population closer to the Anglican church of Saint Tecwyn and the lakes: Llyn Tecwyn Isaf and Llyn Tecwyn Uchaf. The church now stands alone, three-quarters of a mile due east of Cilfor. There is a children's play area at Cilfor, but there are no shops or schools.
The former parish of Llandecwyn stretched from the estuary of the Afon Dwyryd at Pont Briwet to the hills of the Rhinogs. It included the Bryn Bwbach road from Capel Brontecwyn to Eisingrug, a section of the main A496 road between Llandecwyn and Talsarnau, and a section of the main A496 road between Llandecwyn and Maentwrog. It also included land across the River Dwyryd: the area of Cefn Coch and around Rhiw Goch and the road to Llanfrothen. Most of the former parish is now part of the Bro Ardudwy ministry area, which includes Harlech, a few kilometres to the southwest, and Barmouth.
Pen Llandecwyn, the small hill between Saint Tecwyn's church and Llyn Tecwyn Uchaf, is high.
Religious buildings.
The church, dedicated to Saint Tecwyn, lies at an altitude of a little over 150 m, and is the only ancient church in Ardudwy not on the coast (although the present building is Victorian). It has views over the large Dwyryd estuary towards Portmerion. The church only operates for a few services each year, but as part of the national Small Pilgrimage Places network, it marks the end of the 7 km pilgrimage route, Saint Tecwyn's Way. This starts at the church of Llanfihangel-y-traethau to the southwest, which has a window depicting the saint coming ashore in his coracle.
Also within Llandecwyn, there is a Welsh Presbyterian chapel called Bryn Tecwyn which had weekly services until December 2017. This is down on the A496, and is where the bus stop and the village war memorial are located.
Formerly Llandecwyn had other churches. Llenyrch Methodist Chapel was built in 1861 as a Sunday school and was open until the 1920s. It is now a private house. Brontecwyn Chapel (Wesleyan Methodist) was the home of the Llandecwyn Revolt School. The chapel closed in the 1990s and is now a holiday rental cottage. Capel Bach, Brontecwyn, is now a woodstore for a larger house. Capel Newydd (Calvinistic Methodist), was a few yards from Capel Bach, but is now a ruin.
Llandecwyn Revolt School.
Llandecwyn was the focus for a power struggle between the UK Government which was Conservative and largely Anglican, and the local Merionethshire County Council, which was largely Liberal and non-conformist. The Education Act 1902 forced local councils to pay for all schools, including church schools. The council was loath to support the school at St Tecwyn's church, so tried to close it down. A government inquiry followed which decided that Llandecwyn did not need a school. The council in response opened a school, the 'Revolt School', at Brontecwyn Chapel, which rapidly grew larger than the 'National School' at the church. A Liberal landslide in the 1906 general election swept the Conservatives from power, the Revolt School was deemed a success, and the county was given permission to build a new council school at Llandecwyn.
Notable residents.
The local landowners were the Wynn family of Maes y Neuadd, who were descended from the 13th Century Osbwrn Wyddel ('Osborn the Irishman'). They were related to the Oakleys of Tan y Bwlch and the Vaughns of Cors y Gedol.
Other notable residents of Llandecwyn have included:
Mary Evans.
Mary Evans (1735 – 1789), was a mystic and cult leader, known as " (Whitemantle). She was either a servant at Maentwrog rectory, or lived at Breichiau between Llys Tecwyn Uchaf and Ceunant Llennyrch. (Breichiau Copper Mine was located at NGR SH650386). She claimed to be betrothed to Christ, and led a group of followers in ceremonies on Manod Mawr and other hills. Her cult spread to Ffestiniog, Penmachno and Harlech. She died at Talsarnau despite having stated that she would never die, and was buried in Llanfihangel churchyard. Although her followers preserved scraps of her clothing as relics, the sect soon died out.
Ancient monuments.
The impressive ring cairn of Bryn Cader Faner () is one of several ancient sites in the hills within the parish:
Bedd Dorti.
 (Dorti's grave) is a mound alongside the old road from Llandecwyn to Maentwrog, near Llyn Tecwyn Uchaf. The mound is associated with (Dorti the Witch) who lived in the area in the 17th century. According to legend, Dorti was killed by being thrown off the high rocks above Llyn Tecwyn Uchaf in a cask, and she was buried where the cask landed.
The mound is covered with white stones, and there is a tradition that passers-by must add another stone or they will die within a year. A section of the mound has been exposed by passing vehicles, and it is thought that it is a natural mound that was topped by a small cairn of white quartz stones, suggesting that it may be a prehistoric funerary monument.
References.
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