Watch Great Canal Journeys (6/6) live on the web
Timothy West and Prunella Scales return to Wales to explore a canal that has eluded them for more than half a century.
The Monmouthshire and Brecon canal is cut off from the rest of Britain's network of waterways by the Black Mountains, and meanders its way through the tranquil Usk valley.
Along the way the couple visit the old ironworks at Blaenavon, where children as young as five were once put to work, and lend a hand with some lock restoration work.
They also explore the castle at Tretower - which is rumoured to be haunted. Last in the series.
Cast team for Great Canal Journeys (6/6).
No cast for Great Canal Journeys (6/6).
Broadcasts and Catch Up TV for Great Canal Journeys (6/6).
No replays for Great Canal Journeys (6/6) in the next 7 days.
Previous broadcasts on TV
Broadcasts in 2017
On Channel 4
07/12/2017 at 20:00