In 1868, the parish of Llanbleddian contained the following places:
"LLANBLEDDIAN, (or Llanbleithian), a parish in the hundred of Cowbridge, county Glamorgan, 1 mile S. of Cowbridge, its post town, 6 miles from the Cowbridge Road railway station, and 8 S.W. of Cardiff. It is situated on the banks of the river Thaw, commanding a view over the vale and town of Cowbridge. The parish includes the townships of Aberthin and Treinghill. A castle was built here by the St. Quentin family, of which there are some ruins, consisting principally of the chief gateway, with its lofty ivy-mantled towers. Limestone is obtained here. The living is a vicarage in the diocese of Llandaff, value with the curacies of Cowbridge and Welsh St. Donatts annexed, £279, in the patronage of the Dean and Chapter of Gloucester. The church is an ancient edifice, dedicated to St. Bleddian, and contains several very old monuments. The Independents have a chapel, and there is a village school. The parochial endowments produce about £45 per annum, besides £20 left by Sir Leoline Jenkins to be distributed every fourth year among the poor. The principal residences are Llanbleddian Castle, built near the ruins of the ancient seat, Marlborough Grange, Crossways Lodge, and Newton House.
"ABERTHIN, a hamlet in the parish of Llanbleddian, hundred of Cowbridge, in the county of Glamorgan, South Wales, 1 mile N.E. of Cowbridge. The scenery around it is of a pleasing character."
"TREINGHILL, a hamlet in the parish of Llanbleddian, county Glamorgan, 1 mile S. of Cowbridge."