In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Cwm like this:
CWM, or Combe, a parish in St. Asaph district, Flint, 2¼ miles E by S of Rhuddlan r. station, and 2¾ NE by N of St. Asaph. It comprises the townships of Cwm-Isglan and Cwm-Uchglan; and has a post office under Rhyl. Acres, 3, 702. Real property, £3, 907. Pop., 495. Houses, 103. ...
The property is divided among a few. Many points command fine views; and a number of the inhabitants are employed in iron-works. The living is a vicarage in the diocese of St. Asaph. Value, £300.* Patron, the Bishop of Llandaff. The church was reported in 1859 to need repair. Charities, £17.
GB Historical GIS / University of Portsmouth, History of Cwm, in Denbighshire and Flintshire | Map and description, A Vision of Britain through Time.
Date accessed: 26th March 2017
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