River Irthing

The River Irthing runs for about 25 miles through the northern edge of Northumberland, marking the county boundary with Cumbria for its first 15 miles. It begins on Paddaburn Moor in Kielder Forest and winds past Butterburn Flow, a raised bog of special scientific interest. Near Gilsland the river cuts through the Irthing Gorge, a narrow passage flanked by sandstone cliffs. Above the village it drops over Crammel Linn, a 7.6-metre waterfall where peregrine falcons and ravens nest. Old pump-houses from the Blue Streak rocket programme stand just upstream of the falls. Hadrian’s Wall once crossed the Irthing on a bridge at Willowford, half a kilometre east of Birdoswald Roman Fort. The river’s course here is lined with Roman remains linked to the Stanegate road and the Wall. A 914-metre stretch of Wall, including two turrets and the remains of the bridge, runs alongside the river and is now joined to the fort by a footbridge. The availability of stone east of the crossing allowed the Wall to be built more substantially. Downstream the river passes Brampton before joining the River Gelt and then the Eden near Warwick Bridge. The upper reaches show traces of medieval shielings, seasonal shelters used by shepherds. At Gilsland Spa hotel the cliffs give off sulphurous and chalybeate springs, and a petrifying seep can be seen. The river’s banks still bear signs of rapid erosion, with Birdoswald fort’s southern edge under threat and the Roman bridge abutment now 44 metres from the water. The landscape continues to adjust after the last glacial period, leaving a record of both ancient and modern history along the Irthing’s banks.