In 1870-72, John Marius Wilson's Imperial Gazetteer of England and Wales described Llanrhystyd like this:
LLANRHYSTYD, a village, a parish, and a subdistrict, in Aberystwith district, Cardigan. The village stands at the mouth of the river Gwyre, 7 miles SSW of Llanrhystyd-road r. station, and 2 miles SE of Aberystwith; and it has a post office under Carmarthen, and two annual fairs.The parish comprises the townships of Haminiog and Mefenydd. ...
Acres, 8,770; of which 155 are water. Real property, £5,427. Pop., 1,533. Houses, 327. Mabus is the seat of J. L. Phillips, Esq. An ancient castle, called Dinerth, was taken, in 1135, by Owen Gwynedd; was taken again in 1150, by Rhys ap Grufydd; and was taken again, and destroyed, in 1199, by Maelgwyn ap Rhys. A monastic establishment stood at Mynachty. The parish was invaded, in 988, by the Danes. Part of its coast consists of lofty mural cliffs, cut by fissures and pierced with caves. The living is a vicarage in the diocese of St. David's. Value, £140. Patron, the Bishop of St. David's. The church is dedicated to St. Rhystyd, and is recent and handsome.
GB Historical GIS / University of Portsmouth, History of Llanrhystyd, in Ceredigion and Cardiganshire | Map and description, A Vision of Britain through Time.
Date accessed: 26th March 2017
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