The Sea Lock Pound, 1891

The Glamorganshire Canal met the Bristol Channel, and the rest of the world, at the very southern edge of Cardiff where an enlarged section of canal called the Sea Lock Pound was built to accommodate sea-going vessels. Pig iron from Merthyr was transferred to the larger vessels here to continue its journey, access to the Severn Estuary being obtained via a large lock allowing entry and exit at high tide.

This was the oldest section of 'The Docks' and when the industrial focus of the South Wales valleys shifted from iron to coal it quickly became  too small and increasingly larger docks were constructed either side. The old Sea Lock Pound was home to numerous maritime services and small industrial premises along with workers housing and pubs and even hosted the Bute United Rowing Club for a few years in the late 1880s. After the railways took the majority of traffic away from the canal the canal company opened a private railway along the length of the pound in 1899 to connect the businesses with the GWR across Dumballs Road.

Following a long decline traffic ceased on the main canal closed in 1942 due to a breach at Nantgarw  and the entire undertaking was bought by Cardiff Corporation in 1944; the resale value of the land occupied by the canal as it threaded its way through the city centre had not gone unnoticed! Both the Sea Lock Pound and the adjacent Glamorganshire Canal Railway continued to operate though to serve the remaining businesses along this stretch.

The Sea Lock Pound came to an impressive end in December 1951 when the sand dredger Catherine Ethel accidentally hit the inner Sea Lock gates which promptly collapsed. The unfortunate ship was carried out into the estuary on a tidal wave as the whole of the mile long section of canal emptied itself. After the breach the Corporation began infilling the muddy ditch with refuse to create the linear park that survives today. The Glamorganshire Canal Railway continued to operate amongst the dereliction but as the old businesses moved away or closed down traffic dwindled and the line was closed by the Corporation in 1963.



The Sea Lock Pound in 1921

Sources and Further Reading
https://en.wikipedia.org/wiki/Glamorganshire_Canal
https://www.peoplescollection.wales/items/11626 
https://www.peoplescollection.wales/items/11627
https://www.peoplescollection.wales/items/11628
https://www.peoplescollection.wales/items/27609 
The Glamorganshire and Aberdare Canals (Vol.1), Stephen Rowson & Ian L. Wright - Black Dwarf Publications, 2001 Amazon
The Glamorganshire and Aberdare Canals (Vol.2), Stephen Rowson & Ian L. Wright - Black Dwarf Publications, 2004 Amazon
A South Wales Canal and its Railway, Ian L. Wright - Railway Magazine, October 1965