River Honddu

BW

The River Honddu [ hɔnðɨ ] (Welsh Afon Honddu ) is a river in the Black Mountains within the Brecon Beacons National Park, in south-east Wales.

It rises in Powys near the Gospel Pass at the beginning of Ewyas valley through which it flows to the south on to Llanvihangel Crucorney to flow in Monmouthshire. He then changes its direction to the northeast and flows into the River Monnow at the location of the border between Wales and England, where the river suddenly changes its direction. The only significant tributary to the Honddu is the Nant bwch, although flow in the Honddu numerous smaller waters from the steep walls of the Ewyas Valley down.

Probably the Honddu flowed before the last ice age left Llanvihangel Crucorney still further south, but was then deflected by a large terminal moraine, which extends west of the village across the valley. The change in direction of both the Honddu and the Monnow appear with the Neath Disturbance, an ancient fault line runs north of Sugarloaf Mountain towards Hereford through the valley to be related.

The upper river valley has the characteristic U-shape of a valley formed by a glacier. However, it is unclear where the ice came from, that has pulled this deep trench through the eastern Black Mountains. The Honddu is not large enough to have created its own valley. It has been suggested that glacial ice of the River Wye was reached on the Gospel Pass into the Ewyas Valley; nevertheless no boulder clay were found in the valley that would prove by their origin from Central Wales this thesis.

In the valley lies Llanthony Priory, a popular attraction for many visitors to the national park. At the lower end of the Ewyas Valley, a Cwmyoy, which is known for its church, which is deformed by the slow movement of the slope on which it stands. The entire village is built on an old landslide that is not completely inactive.