This bridge which dates from 1793 and spans the River Taff is the world's oldest cast-iron railway bridge.
It also supported two water troughs, a lower feeder just below the decking and an upper aqueduct above the decking at a height of 80ft above the river. The name means bridge of troughs.
The bridge was built to supply the nearby Cyfarthfa Ironworks. Limestone was carried along the 4ft gauge horse drawn tramroad which is still visible on the bridge. The lower water trough supplied the ironworks whilst the upper aqueduct supplied a 50ft water wheel that delivered a cold air blast to the furnaces.
The main bridge was constructed in iron; the A-frame based on previous timber-working practices. The aqueduct was a wooden trough.
The bridge is accessible from the south-west via the Taff Trail and from the north-east via a small industrial estate near to Cyfarthfa Park.
It is a Scheduled Ancient Monument and also Grade II Listed.
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