The church was erected in the 13th century and then thoroughly restored and probably expanded at the end of the 15th or the beginning of the 16th century. It was recorded for the first time in a document from 1254. In the 17th century, the porch and the belfry were added. The building underwent minor renovations in the 19th and 20th centuries.
The church was erected on the terrain sloping towards the sea, between the coastal trail and the cliff edge. The original building was probably smaller than the present one, but it consisted of a rectangular nave and a chancel, as it is today, forming one whole and covered with one roof. The entrance to it led through a simple, pointed northern portal.
In the 15th and 16th centuries, the walls were raised and the building was enlarged towards the west. The windows were probably widened at that time, from narrow, almost slit, to single and two-light, closed with trefoils, inserted into four-sided jambs. The roof and the roof truss were also replaced (the current one was dendrochronologically dated to the years 1502-1539). Inside, the nave was separated from the presbytery by a rood screen.
The porch on the south side of the present church is already an early modern addition, although there are opinions about its late medieval origin. A large part of the windows was transformed in the 18th and 19th centuries, but the late Gothic south window and the west slit opening, perhaps from the 13th century, have been preserved. Inside, there is a late-medieval roof truss. The currently preserved rood screen has only some medieval fragments.
Salter M., The old parish churches of North Wales, Wolverhampton 1993.
Wooding J., Yates N., A Guide to the churches and chapels of Wales, Cardiff 2011.
Website coflein.gov.uk, St Celynnin’s church, Llangelynnin.