LLANTILLIO-CROSSENNY, a village and a parish in the district and county of Monmouth. The village stands on the river Trothy, 5 miles NW by N of RaglanFootpath r. station, and 7 WNW of Monmouth; and has a post office under Abergavenny. The parish comprises 5,951 acres. Real property, £5,886. Pop., 748. Houses, 160. The property is divided among a few. LlantillioCrossenny House belonged to the Powells, passed to the Lewises, and belongs now to Col. Clifford. Vestiges of an ancient fortified house, said to have been the residence of Sir David Gam, are to the N of the park. Castell Gwyn, or White Castle, stands on an eminence 1½ mile to the N; is said to have been occupied by Sir Gwyn ap Cwarthvold at the time of the Norman invasion; continued to be a place of note so late as the time of Elizabeth; and is a large oval structure, with six bastions, and well preserved outer-works. The living is a vicarage in the diocese of Llandaff. Value, £270.* Patrons, the Dean and Chapter of Llandaff. The church is dedicated to St. Teilaw; is principally decorated English, with a lofty tower, and in good condition; and includes a large chapel, chiefly later English, on the N side of its presbytery. The churchyard contains an altar-tomb to the son of Col. Clifford. There are a grammar school, with £150 a year from endowment, and other charities £40.

(John Marius Wilson, Imperial Gazetteer of England and Wales (1870-72))