In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Rhyd Y Bryw like this:
RHIDYBRIW, or Ysclydach, a chapelry in Llywell parish, Brecon; on the river Usk, and on the Brecon and Llandovery railway, 2½ miles E of Trecastle. Post-town, Trecastle, under Brecon. Rated property, £1, 652. Pop., 303. Houses, 64. The property is much subdivided. The living is a p. curacy in the diocese of St. Davids. Value, £145. Patron, the Vicar of Llywell. The church is good.
Additional information about this locality is available for Is Clydach
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 Rhyd Y Bryw has changed, please see our redistricted information for the modern district of Powys. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Rhyd Y Bryw and units named after it.
GB Historical GIS / University of Portsmouth, History of Rhyd Y Bryw, in Powys and Brecknockshire | Map and description, A Vision of Britain through Time.
Date accessed: 13th December 2013
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