In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Llanddyfnan like this:
LLANDDYFNAN, a parish, with a village, in the district and county of Anglesey; near the river Cefni, and down to Red Wharf bay, 2 miles W of Pentraeth, 6½ W by N of Beaumaris, and 6¼ NNW of Menai-Bridge r. station. Post town, Pentraeth, under Menai-Bridge, Anglesey. Acres, 3,506; of which 25 are water. ...
Real property, £2,664. Pop., 720. Houses, 168. The property is divided among a few. Llanddyfnan Place is a chief residence. Some common lands were enclosed between 1851 and 1861. Limestone abounds and is worked. Traces exist of a Roman road; and a large maenhir is near the church. The living is a rectory, united with the p. curacy of Llanfair-Mathafarn-Eithaf, in the diocese of Bangor. Valne, £280. Patron, the Bishop of Bangor. The church is dedicated to St. Dyvnan, and was rebuilt in 1847.
Llanddyfnan is now part of the Isle of Anglesey district. Click here for graphs and data of how the Isle of Anglesey has changed over two centuries. For statistics about Llanddyfnan itself, go to Units and Statistics.
GB Historical GIS / University of Portsmouth, History of Llanddyfnan in The the Isle of Anglesey | Map and description, A Vision of Britain through Time.
Date accessed: 30th April 2017
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