In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Llanfairfechan like this:
LLANFAIRFECHAN, a village and a parish in Bangor district, Carnarvon. The village stands on the coast, adjacent to the Chester and Holyhead railway, under Penmaen-Mawr, 6½ miles E by N of Bangor; is a pretty place; and has a station on the railway, and a post office‡ under Bangor. ...
The parish comprises 4,255 acres of land, and 2,266 of water. Real property, £2,822. Pop. in 1851,809; in 1861,1,199. Houses, 234. The increase of pop. arose from the extension of stone quarrying, the influx of summer visitors, and extensive improvements effected by J. Platt, Esq. The property is much subdivided. Most of the water area is in the Laven sands. Penmaen-Mawr rises to the altitude of 1,545 feet; projects boldly to the shore; presented serious difficulties to the forming of the railway round its foot; and is crowned by the ancient British fort of Braich-y-Ddinas, with traces of circular uncemented stone walls about 12 feet thick, and traces also of cyttiau. The living is a rectory in the diocese of Bangor. Value, £430.* Patron, the Bishop of Bangor. The parochial church is good; and there is a chapel of ease for service in English.
GB Historical GIS / University of Portsmouth, History of Llanfairfechan, in Conwy and Caernarvonshire | Map and description, A Vision of Britain through Time.
Date accessed: 27th April 2017
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