Crumlin Arm (Monmouthshire canal)

The Crumlin Arm of the Monmouthshire canal is part of the Monmouthshire & Brecon Canal network in South Wales. It connected Crumlin and its tramways to the Docks at Newport.

The Crumlin to Abercarn section opened in March 1794 and two years later the branch was open except for Fourteen Locks. It was not until April 1799 that the proprietors (shareholders) declared that the canal was finally complete. The branch was 11 miles (18 km) long, rising 358 ft (109 m) through 32 locks.

The canal started at a basin in Crumlin and ran through the villages of Newbridge, Abercarn and Cwmcarn now under the A467. The canal then reached Cwmcarn lock now under the grass at the end of the present canal. The canal crosses the Pontywaun aqueduct and follow the side of the mountain above Crosskeys and Risca this section is the longest lock-free pound on the system until the Fourteen Locks. The canal descends the fourteen locks and turns sharp along the hill side. The canal now flows next to the M4 into urban Newport to Barrack Hill tunnel (now disused and culverted). The rest of the canal through the city is lost beneath modern roads and buildings. The Kingsway dual carriageway follows the route of the canal to the now-filled-in Old Town Docks near the Transporter Bridge.

These were originally numbered (as were bridges) by the usual system of top down. Therefore, Cwmcarn lock was number 12. The GWR renumbered the locks (and bridges) from Newport to Crumlin and then up the Main Line to Brecon. Thus, Cwmcarn lock became Lock 22. Lock 22 was under the grass area just beyond the end of the canal. Going down was a lock-free pound to the top of Fourteen Locks and going up was another pound to Abercarn bottom lock below the old Prince of Wales Colliery.

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