Clydai 3 is a roman-letter and ogam-inscribed, and cross-icised stone, first recorded in 1698, when it was lying inside Eglways Trisant (NPRN 422372) in the churchyard of St Clydai's Church (NPRN 421735). By 1859 it had been removed to Dygoed Farm (some 1.5 miles to the north-east) where it was set into the foot of steps leading to the granary. It is now clamped to the west wall of the south aisle, adjacent to Clydai 1 (NPRN 422368) and Clydai 2 (NPRN 422370). The cross is the correct way up and the inscriptions are upside down.

The stone is a rough, irregular slab of volcanic rock. Measurements are given as 146cm x 27 < 42 > 38cm width x 13cm diameter. It was first used as a roman-letter Latin- and ogam-inscribed stone, and later upended for reuse as a cross-carved stone. The Latin inscription on face A has been translated as `of Dob[?]tucus son of Evolengus?. The ogam letters are incised on the angle of the faces A and B, reading upwards. It reads `DOVAT[.]C[?]S. Both inscriptions are thought to date to the late 5th or first half of the 6th century. Towards the opposite end of face A is a cross carved in low false relief. It is thought to date to the late 7th or 8th century.

Sources include:
Edwards, N. 2007, Corpus of Early Medieval Inscribed Stones and Stone Sculpture in Wales

N Vousden, 21 November 2017