In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Treuddyn like this:
TREDDYN, or Tryddyn, a chapelry in Mold parish, Flint; 4 miles S by E of Mold r. station. It has a post-office under Mold. Real property, £11,156; of which £7,200 are in mines. Pop., 1,525. Coed-Talwn collieries and iron-works are here, and have a branch railway for minerals to Padeswood r. station. The living is a p. curacy in the diocese of St. Asaph. Value, £140.* Patron, the Bishop of St. A.
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 Treuddyn has changed, please see our redistricted information for the modern district of Flintshire. More detailed statistical data are available under Units and statistics, which includes both administrative units covering Treuddyn and units named after it.
GB Historical GIS / University of Portsmouth, History of Treuddyn in Flintshire | Map and description, A Vision of Britain through Time.
Date accessed: 26th April 2015
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