OLDCASTLE, a parish in the lower division of the hundred of ABERGAVENNY, county of MONMOUTH, 8 miles (N. by E.) from Abergavenny, containing 67 inhabitants. The living is a perpetual curacy, in the archdeaconry of Brecon, and diocese of St. David's, endowed with £400 private benefaction, and £600 royal bounty, and in the patronage of the Earl of Oxford. The church is dedicated to St. John the Baptist.