The church contains a stone sundial, dated 1689, which was originally set up by Lady Magdalen Probert of the Argoed, Penallt.
The stones form an approximate line running between north-east and south-west at an azimuth of about 229°, which probably indicates the midwinter sunset,[REF] though the midsummer sunrise cannot be excluded on account of the lack of precise alignment of the stones [REF].