In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Oldcastle like this:
OLDCASTLE, a parish in Abergavenny district, Monmouth; on the river Monnow, at the boundary with Herefordshire, and under the Black mountains, 1½ mile N W of Pandy r. station, and 7 N by E of Abergavenny. It has a post-office under Abergavenny. Acres, 922. Real property, £649. Pop., 60. Houses, 11. The property is all in one estate. An old castle was here, on aspot now occupied by a farm-house; and has left butslight remains. Sir John Oldcastle was a resident. There are several Roman camps; and Roman coins have been found. The living is a rectory in the diocese of Llandaff. Value, £73. Patron, E. Higginson, Esq. The church was reported in 1859 as not good.
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 Oldcastle has changed, please see our redistricted information for the modern district of Monmouthshire. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Oldcastle and units named after it.
GB Historical GIS / University of Portsmouth, History of Oldcastle in Monmouthshire | Map and description, A Vision of Britain through Time.
Date accessed: 12th December 2013
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