Not to be confused with the Monnow tributary, this Honddu begins life at Blaenhonddu on the Eppynt, a mountain dividing the Brecon Beacons and the Cambrian Mountains, flowing in a southerly direction to join the Usk at Brecon, or Aberhonddu. The river’s name derives from the Welsh for easy, happy or pleasant, an appropriate description for this picturesque trout stream.