Pencader Tunnel

Pencader Tunnel is an abandoned railway tunnel on the old trackbed of the Carmarthen to Aberystwyth main line in south-west Wales. It was originally bored for the Llanpumsaint-Pencader section of the Carmarthen and Cardigan Railway (C&CR). It is approximately 988 yards (903 m) long (just over half-a-mile), making it the longest tunnel in West Wales and is bored through Ordovician shales. It is single-track and built to the C&CR's adopted broad gauge dimensions, as opposed to the smaller standard gauge used on Britain's railways today. It is also known as alternatively Alltwalis Tunnel and Dolgran Tunnel to local villagers.

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Tunnel data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).

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