In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Llanfair Ar Bryn like this:
LLANFAIRARYBRYN, a parish and a sub-district in Llandovery district, Carmarthen. The parish lies on the Sarn Helen way, on the Llandovery and Knighton railway, and on the rivers Bran and Towy, at the S end of Cilcurn forest, 1 mile N of Llandovery; has a post office of the name of Llanfair, under Carmarthen; and contains the hamlets of Rhandir-Abbot, Rhandir-Isaf, Rhandir.Canol, and Rhandir-Uchaf. Acres, 23,457. Real property, £9,405; of which £2,500 are in mines. Pop. in 1851,1,705; in 1861,1,559. ...
Houses, 303. The property is not much divided. There are lead mines, belonging to the Earl of Cawdor. A Roman camp is on an eminence round the site of the church, and has furnished Roman coins, bricks, and other relics. The name Llanfairarybryn signifies ' ' Mary church on a hill. ''The living is a vicarage, annexed to the vicarage of Llandingat, in the diocese of St. David's. The church is tolerably good.The sub-district is conterminate with the parish.
A Vision of Britain through Time includes a large library of local statistics for administrative units. For the best overall sense of how the area containing Llanfair Ar Bryn has changed, please see our redistricted information for the modern district of Carmarthenshire. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Llanfair Ar Bryn and units named after it.
GB Historical GIS / University of Portsmouth, History of Llanfair Ar Bryn in Carmarthenshire | Map and description, A Vision of Britain through Time.
Date accessed: 29th September 2016
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