St David's at Llanddew, a few miles north of Brecon, is the oldest church in the county of Brecknock. The building dates from the 13th Century and is in a cruciform shape, with a central tower. Llanddew was a 'clas' church - a mother church with monastic buildings. A community of canons lived there, and travelled around the local area preaching and celebrating communion under a cross in the open air.