Twmpa
 Twmpa or Lord Hereford's Knob is a mountain in south-east Wales forming a part of the great northwest scarp of the Black Mountains. It lies 3 km west of the border with England and around 7 km south of Hay-on-Wye. To the northeast lies the Gospel Pass through which runs a minor road between Hay and the Llanthony Valley. A ridge known as Darren Lwyd tapers away for about 3km to the southeast of the summit.