In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Garthbrengi like this:
GARTHBRENGY, a parish in the district and county of Brecon; on the river Honddu, 3 miles N of Brecon town and r. station. Post town, Brecon. Acres, 2, 001. Real property, £678. Pop., 162. Houses, 35. The property is divided among a few. The surface rises. abruptly from the Honddu. The living is a vicarage in the diocese of St. Davids. Value, £102. Patron, the Bishop of St. Davids. The church is ancient; and the roof of it was recently in bad condition.
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 Garthbrengi 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 Garthbrengi and units named after it.
GB Historical GIS / University of Portsmouth, History of Garthbrengi, in Powys and Brecknockshire | Map and description, A Vision of Britain through Time.
Date accessed: 25th May 2013
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