In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Tredogan like this:
TREDOGAN, a village in Penmark parish, Glamorgan; 5½ miles SE of Cowbridge.
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 Tredogan has changed, please see our redistricted information for the modern district of The Vale of Glamorgan. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Tredogan and units named after it.
GB Historical GIS / University of Portsmouth, History of Tredogan in The Vale of Glamorgan | Map and description, A Vision of Britain through Time.
Date accessed: 20th June 2013
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