In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Trevethin like this:
TREVETHIN-popularly Trebden- a parish in Pontypool district, Monmouth; nominally 1 mile NNE of Pontypool r. station, but containing Pontypool town, which has a head post-office. Acres, 11,329. Real property, £57,320: of which £4,160 are in mines, £13,900 in ironworks, £34 in quarries, £347 in railways, and £187 in gasworks. Pop. in 1851, 16,864; in 1861, 18,146. Houses, 3,571. The property is much sub-divided. The living is a vicarage in the diocese of Llan-daff. Value, not reported.* Patrons, the Dean and Chapter of L. The church was restored in 1847. The p. curacies of Abersychan and Pontnewnydd are separate benefices. See Pontypool.
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 Trevethin has changed, please see our redistricted information for the modern district of Torfaen. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Trevethin and units named after it.
GB Historical GIS / University of Portsmouth, History of Trevethin, in Torfaen and Monmouthshire | Map and description, A Vision of Britain through Time.
Date accessed: 19th May 2013
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