Llangynidr locks and pond

Llangynidr locks and pond

The Monmouthshire & Brecon Canal changes level at Llangynidr with a flight of five locks. This is the most rapid change in level on the section of the canal which is navigable today. The canal opened from Gilwern to Llangynidr in 1797 but the continuation to Talybont, including the flight of locks, was not completed for another two years. The lowest locks are near the village.

The top two locks are so close together that a balancing pond is needed to prevent major changes in the water level when a boat passes between the locks. You can see the pond north of the towpath. It’s connected to the canal by a culvert under the path.

Each lock has gates at both ends of a stone-lined chamber. Water is emptied from the chamber to lower a boat, or poured into the chamber to raise a boat to the canal’s upper level. At Llangynidr, the upstream end of each lock has a single gate while the downstream end has a pair of gates.

The canal occasionally had to be cleaned, to prevent sedimentation and debris making it too shallow for boats. When cleaning the canal at Llangynidr in 1910, a group of c.18 men found a hoard of gold sovereigns from the reign of King George III (when the canal was created). Once the first coins were revealed, other workers scrambled to find more – but none of them got rich. The Great Western Railway, which owned the canal, took the treasure and soon received claims from local residents who insisted they were the coins’ rightful owners!

The second bridge west of the locks is known as Workhouse Bridge. The workhouse provided accommodation and work for paupers. The building, on the south side of the canal before the bridge, is now a private house.

The navigable section of the Monmouthshire & Brecon Canal is looked after by the charity Glandwr Cymru the Canal & River Trust in Wales.

With thanks to the archive of the Monmouthshire, Brecon and Abergavenny Canals Trust

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Canal & River Trust website – Monmouthshire & Brecon Canal

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