However, there is no evidence that Pabo, a 5th-century prince, lived in the area and the tradition that he founded the church has little supporting basis.

[5] A stone slab gravestone dating from the late 14th century, made from Flintshire sandstone, was found in about 1680: according to the 17th-century Welsh historian Lewis Morris, it was unearthed by a sexton digging a grave in the churchyard.

[4][6] The rectangular slab (from the same workshop as one at Bangor Cathedral and one of St Iestyn at St Iestyn's Church, Llaniestyn, given the similarities between them)[6] has a shallowly engraved full-length image of a bearded man wearing a crown and a loose, pleated tunic over a garment reaching to his wrists.

He holds a sceptre in his right hand; his head is on a cushion underneath an arch, and the background is decorated with flowers.

The inscription, which is incomplete, reads "Hic iacet Pa[bo] Post Priid" (or "Prud") – "Here lies Pabo the Pillar of Britain".

[5] The church stands alongside a minor road between Llanddeusant and Rhosgoch, near the Llyn Alaw reservoir.

The east wall and window, with stone tracery and an ogee-topped light in a pointed arch, are from the 14th century.

[7] Chevron-carved voussoirs (wedges) and three stone human heads, weathered by time and also probably from the 12th century, have been repositioned over the doorway, which is at the west end of the south side of the church.

[6] Inside, as well as the Pabo monument on the north wall, there are medieval arched trusses and two 18th-century marble memorials.