Former De Winton foundry, Caernarfon

Link to French translationFormer De Winton foundry, St Helen’s Road

This building was once the erecting shop of the De Winton foundry, which made equipment for quarries and ships. It is well-known among rail enthusiasts for its unusual vertical-boiler locomotives, one of which is on display at Dinas station.

The company was formed in 1854 by Owen Thomas, who already ran a thriving foundry business here, and marine engineer Jeffreys Parry De Winton. Their premises, known as the Union Ironworks, comprised a string of buildings along St Helen’s Road. The surviving building to the west of the erecting shop, with its decorative window and door surrounds, was the drawing office.

The company traded as Thomas & De Winton until Mr Thomas died in 1866, after which it was De Winton & Company. It made boilers and other parts for many of the steam ships which docked in Caernarfon.

The foundry’s exports went as far afield as North America and India, while the burgeoning quarries of Gwynedd bought saw tables (for cutting slates) and many other cast-iron implements from De Winton. A large waterwheel, made here in 1870, is preserved in working order at the former slate workshops in Llanberis, now the National Slate Museum. Another De Winton waterwheel survives at the former Penrhyn Quarry workshops in Bethesda.

Mr De Winton served as Caernarfon’s mayor for two years, and died in 1892. The foundry’s trade declined in the late 19th century, as slate exports reduced and fewer ships came to Caernarfon. The foundry closed c.1901. The former erecting shop is now home to Oakmere Plumbing.

Where is this HiPoint?

Postcode: LL55 2YD

Information on giant water wheel (National Slate Museum website)

Website of Oakmere Plumbing

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