The village of Llandyrnog is situated on the B5429, some three and a half miles south east of Denbigh. According to Clwyd Powys Archaeological Trust, it is 'one of several historic settlements that developed along the eastern flank of the Vale of Clwyd, with the river itself little more than one kilometre to the west and the Clwydians rearing up 2km to the east.'
'The earliest document referring to the church of St Teyrnog (or Tyrnog) is the Norwich Taxation of 1254 which lists Landernauc. In 1291 it was Llandurnok, Llandyrnok in 1423 and it achieved its modern form in the middle of the 17th century. With only a single dedication to this saint in Wales, there can be no certainty as to the precise form of the name, though it has been suggested that the saint may have been of Irish origin. Tradition has it that the church dedication commemorates a 6th-century saint and at least a part of the churchyard's shape is sufficiently curvilinear to suggest an early medieval origin.'
'By the mid-19th century a small nucleation had developed at the crossroads south of the church. The tithe map hints at a rather wider street south of the churchyard which at that time was being infilled, and its presence might in turn suggest a small market place. But there is no other evidence to collaborate this 'market area', and given the proximity of Denbigh only 5km away it seems unlikely. Furthermore there must be some doubts about the antiquity of the B5429. Its course in the vicinity of the village, cutting through the north-west/south-east axis of the former open fields implies a late insertion into an already existing layout. The minor lane running up from the river and passing on to Llangwyfan then takes the role of the major thoroughfare through the village.'
'The pattern of the medieval open fields (though not the fields themselves) is retained to the present day in the layout of enclosures around the village. The pattern is even more obvious on 19th-century Ordnance Survey maps, emphasising the north-west/south-east axis of the medieval strips.'
Notable historic buildings in the village include the church (NPRN 165389), which dates from the 15th century, and 4 and 5 Church Square, which are 'cottages which could perhaps date back to the 17th century. They constitute the surviving part of a larger group of cottages which in 1839 were said to be cottages in the village occupied by 'paupers and others', suggesting that they could have functioned as almshouses.'
In addition to St. Teyrnog's church, Llandyrnog had two places of worship. Felin Isa Baptist chapel (NPRN 7664) was built on the south western edge of the village in 1836, but had fallen into disuse by 1980. The Wesleyan Methodist chapel (NPRN 7666) is nearer the centre of the village. It was first built in 1810, and appears to still be in use as a chapel.
The first edition of the 25inch OS maps, published in 1875, shows that the village had two public houses - the Golden Lion and the White Horse. Both were still open at the time of writing. Although the National School (NPRN 419152) that also appears on the map has closed, there is still a primary school at Llandyrnog. Ysgol Bryn Clwyd educates approximately 30 pupils from the ages of three to eleven, and is part of a federation with Ysgol Gellifor. Similarly, the post office identified on the map in 1875 remains open as part of the village store.

Sources: modern and historic OS maps; google street view; Clwyd Powys Archaeological Trust Report No 1257 - 'Historic settlements in Denbighshire,' by R J Silvester, C H R Martin and S E Watson. Published in March 2014 (p. 65-66); Estyn report on YSgol BRyn Clwyd published in February 2017; Coflein database
M. Ryder, RCAHMW, 7th January 2019