In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Cwm like this:
CWM, a township in Meiford parish, Montgomery; 5¼ miles NW of Welshpool. Pop., 29.
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 Cwm 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 Cwm and units named after it.
GB Historical GIS / University of Portsmouth, History of Cwm, in Powys and Montgomeryshire | Map and description, A Vision of Britain through Time.
Date accessed: 25th May 2013
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