 It is the seat of the Bishop of Llandaff, whose diocese within the Church in Wales covers the most populous area of Wales.Most of the history of Llandaff centres on its role as a religious site.Before the creation of Llandaff Cathedral, it became established as a Christian place of worship in the 6th century AD, probably because of its location as the first firm ground north of the point where the river Taff met the Bristol Channel, and because of its pre-Christian location as a river crossing on a north–south trade route.