In 1868, the parish of St Lythans contained the following places:
"ST. LYTHAN'S, a parish in the hundred of Dinas Powis, county Glamorgan, 6 miles S.W. of Cardiff, its post town. The living is a vicarage* in the diocese of Llandaff, value £199, in the patronage of the archdeacon. There are remains of a cromlech. Dyffryn is the only seat."
"DYFFRYN, a village in the parish of St. Lythan's, in the county of Glamorgan, 5 miles S.W. of Llandaff It is situated near Dyffryn House, the ancient family seat of the Prices. Here are several cromlechs, the one at St. Nicholas being considered the largest in Britain. The upper stone measures 24 feet by 17."