In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Pennant like this:
PENNANT, a township in Llanbrynmair parish, Montgomery; on the stream of the Ffrwd-y-Pennantwaterfall, 9½ miles N W of Llanidloes. Real property, £1, 527; of which £50 are in mines. Pop., 363. The waterfall here makes a descent of 130 feet.
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 Pennant 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 Pennant and units named after it.
GB Historical GIS / University of Portsmouth, History of Pennant, in Powys and Montgomeryshire | Map and description, A Vision of Britain through Time.
Date accessed: 21st May 2013
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