Chapel of St. Deniol was probably erected in the 12th century in the area of a small monastery dating back to the beginning of the 6th century. After the disappearance of the Celtic monastery, this place was taken by a group of nuns from Aconbury in Herefordshire. The monastery was dissolved by Henry VIII in 1534, its buildings became the residence of clergy of the local parish church, and the chapel with time fell into disrepair.
The chapel is a simple and small, aisleless building with a crypt.
Website wikipedia.org, Penally Abbey.