River Irt
The River Irt is a river in the county of Cumbria in northern England. It flows from the south-western end of Wast Water, the deepest lake in England, leaving the lake at the foot of Whin Rigg, the southern peak of the famous Wastwater Screes.
On its short journey to the coast, the Irt is crossed by the Cumbria Coastal Way long distance footpath, at Drigg Holme packhorse bridge. The Irt flows through the Drigg Dunes and Irt Estuary Nature Reserve before joining the River Esk and River Mite at Ravenglass.
In the 19th century the River Irt was famous for the extremely rare black pearls that grew in its freshwater mussels. Poaching of the pearls is thought to have led to the mussels becoming extinct in the River Irt.
Coordinates: 54°22′N 3°25′W / 54.367°N 3.417°W
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