Wentlooge sea wall
This sea wall stretches from near the mouth of the river Rhymney almost to the mouth of the Usk near Newport. It’s a vital part of the drainage system which has allowed the low-lying Wentlooge levels to be farmed for many centuries.
Remains of a Roman sea defence have been found near here, and at two locations further east. Elsewhere the sea wall generally follows the line, a little further inland, where sea defences were rebuilt in medieval times after centuries of neglect. Remnants of the later wall are visible behind the noticeboard here.
Archaeologists have discovered remains from earlier civilisations on the levels, but it’s likely that Roman soldiers based at Caerleon (north of Newport) were the first to build a wall to stop indundation from the sea. Reens – ditches criss-crossing the land – turned marshland into fertile farmland.
The Glamorgan-Gwent Archaeological Trust believes the Romans may have grazed their cavalry horses in the area. Many horse bones from the period have been excavated at Rumney Great Wharf, where there was a Roman settlement.
In 1607 the levels were flooded by a tidal wave which swept up the Bristol Channel, killing hundreds of people.
The tidal range here is the second highest in the world, with high tide c.15m (49ft) above low tide. This creates a large inter-tidal feeding area for birds. Species to look out for include dunlin, curlew, oystercatcher, redshank, shelduck and teal.