Westbury-on-Trym, now on the outskirts of Bristol but predating the city, has its origins in a grant of land given by King Offa of Mercia to Æðelmund, eoldermann of the Hwiccae, in the late 8th century. There has been a church on the same site for almost the whole of its history, probably a Benedictine priory to begin with, and later the collegiate church for Westbury College of Priests after 1194.
John Carpenter, then Bishop of Worcester, extended the buildings in 1447, intending for it to become a co-cathedral with the one in his diocesan seat. Carpenter was buried in the church, which he rededicated to the Holy Trinity, after his death in 1476.
In 1544, after the dissolution of the monasteries. the residential buildings were turned into a private dwelling by Sir Ralph Sadler, Henry VIII’s Master of the Great Wardrobe and former Secretary of State.
Most of of the College of Priests was burned down by Prince Rupert during the Civil War in order to prevent its use by Parliamentarian forces. Today, all that remains is its gatehouse, a grade I listed building maintained by the National Trust. The remains can be viewed along College Road, BS9 3EH. If using public transport, take bus no 1, 11, 11A, 77 or 508 to Westbury Village (the gatehouse is about 4 minutes walk from the bus stop). Tours of the building are available, by prior arrangement with the National Trust.