We explore the Victorian canal that feeds Cardiff's port
in today's modern age, one port in Wales continues to rely on a piece of technology that is hundreds of years old.
Cardiff Port depends on its Victorian feeder canal to keep it topped up with water.
It runs right beneath the capital and saves the port thousands of pounds.
Watch the report from James Crichton-Smith below:
Walking along the Taff trail, it's easy to miss. But by the bridge at blackweir, some of the River Taff's water is diverted - it's heading for the port.
The canal is around three and a half miles long.
From Bute Park, it heads for the city centre...
It turns sharply at the castle before going underground - decending around 9 feet along its course.
It's only visible from the surface a couple times as it winds beneath the city streets.
The canal finally emerges at the northern end of the Bute east dock.