The Monmouthsire & Brecon Canal runs north from Cwmbran through the villages of Sebastopol and Grffithstown towards Pontypool and the north. It seems pretty clear these days on the stretches I've walked, very occasionally seeing people fishing. To what extent it is worth making a day of it fishing I wouldn't know. Suggest you get on a fishing m/b and ask before making the decision to travel northward. Goytre Wharf is quite a nice location though for a quiet afternoon. The Goytre Angling Club fishes between bridges 73 & 77 according to the website.
https://www.goytrewharf.com/
https://canalrivertrust.org.uk/enjoy...d-brecon-canal
StT.
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