In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Llandyrnog like this:
LLANDYRNOG, a village, a parish, and a sub-district, in Ruthin district, Denbigh. The village stands about a mile from the river Clwyd, under Bryn-y-Cloddian, 3¼ miles E of Denbigh r. station; and has a post office under Denbigh.The parish comprises the townships of Ystrad, Banker, Caerfedwin, Cwmdylluan, Llan-Rhiwbebyl, and Speddyd. ...
Acres, 3,223. Real property, £4,289. Pop., 655. Houses, 140. The property is divided among a few. Glanywern is the seat of Lieut. Col. Madocks. Vron Iw was the seat of the Madocks family, and is now a farm-house. An ancient British camp is on Bryn y-Cloddian. The living is a rectory in the diocese of St. Asaph. Value, £666. * Patron, the Bishop of St. David's. The church is dedicated to St. Tyrnog, and is good. Charities, £15.--The subdistrict contains also two other parishes, and part of another. Acres, 10,068. Pop., 1,826. Houses, 406.
GB Historical GIS / University of Portsmouth, History of Llandyrnog in Denbighshire | Map and description, A Vision of Britain through Time.
Date accessed: 23rd March 2017
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