St. Eigen's church, 2 miles south-west of Hay, is set in an ancient nearly circular churchyard. It is dedicated either to a daughter of Caractacus, who lived in the parish, or to St. Eigen, Bishop and Confessor.

Most of the church fabric is 15th to 17th century, with traces of Norman work. The 14th century south porch has an upper storey, once the living quarters of the priest but now housing three bells all dated 1670.

On the porch floor is the old Norman font, found in the churchyard, and a smaller quern, (hand mill). The nave and chancel are on one level, the numbered pews there have doors to prevent draughts.

During the 1857 restoration the barrel organ, now at the west end, was replaced by a new organ. The former east window was set in the west wall, a new east window added and the chancel arch rebuilt. The 18th century two-decker pulpit was divided, one half becoming the priest's stall. The 17th century altar and altar rails remain.