This is the original track bed of the Ffestiniog Railway just north of Dduallt Station. The creation of Tanygriaiau Reservoir as part of a pump storage scheme flooded the original route. Undaunted the society realigned the route to be high enough to bypass the new lake - a spiral line at Dduallt to gain height and then cuttings, tunnels along with a couple of miles of new trackbed.
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