In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Llanfair Is Gaer like this:
LLANFAIR-IS-GAER, a parish in the district and county of Carnarvon; on the Menai strait and on the Carnarvon railway, 2¼ miles NE by N of Carnarvon. It contains the village of Brynffynon and the seaport village of Port-Dinorwig, the latter of which has a post office under Carnarvon. Acres, 2,474; of which 565 are water. Real property, £2,312. Pop. in 1851,687; in 1861, 1,060. Houses, 201. The increase of pop. arose from the extension of slate quarrying; and 120 of that in 1861 were persons on board vessels. ...
The property is divided among very few. Plâs-Llanfair is a chief residence. Port-Dinorwig is a shipping place for slates from the Snowdonian quarries; and is reached, through the parish, by a tram railway. A Roman camp was on the coast, immediately above the site of the church; and hence the name Llanfair-Is-Gaer, which signifies ''Mary church under a fort. ''Agricola crossed hence to Anglesey. The living is a p. curacy in the diocese of Bangor. Value, £77. Patron, the Bishop of Bangor. The church was rebuilt in 1865; is in the early English style, of local stone, faced with Newry granite and with Wrexbam stone; comprises nave, transept, and chancel, with vestry and bell-turret: and has a memorial E window to the late J. G. Griffith. Esq.
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 Is Gaer has changed, please see our redistricted information for the modern district of Gwynedd. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Llanfair Is Gaer and units named after it.
GB Historical GIS / University of Portsmouth, History of Llanfair Is Gaer, in Gwynedd and Caernarvonshire | Map and description, A Vision of Britain through Time.
Date accessed: 10th December 2013
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