This is ruined late sixteenth century church that was never completed.

A magnificent new church, the largest of its age, was begun in 1578-9 by Robert Dudley, Earl of Leicester in the walled upper town of Denbigh (NPRN 15235). This would have superseded St Hilary's Chapel (NPRN 94724) and there is a tradition that it was intended to to be a new Cathedral Church for the diocese of St Asaph. In the event work was suspended in 1584 due to a lack of finance, and the church was never completed.

Robert Dudley was a leading figure in the Puritan reform movement and the church was built as a Protestant preaching hall, modelled to reflect the new form of services where the preaching of the word, and theerfore the pulpit, formed the focus rather than the altar. It would have been a great ten bay aisled building, 55m by 23m, with no structural division between the nave and chancel.The exterior was intended to be Gothic in style, the interior classical, with arcades of alternating single and paired Tuscan columns.
The church is of interest in being the first large church begun after the Reformation and would have been a fine specimen of the Italian Renaissance which was just beginning to replace Gothic. It is sometimes referred to as Old St David's.

Sources: Butler in the Journal of the British Archaeological Association 37 (1974), 40-62
'Denbigh Castle, Town Walls & Friary' DoE guide (1976), 36-39
CADW Listed Buildings Database (ref:970)
D.R.Thomas, History oif the Diocese of St Asaph vol.2 (1911), p.21