In this case the name is the result of a mistake made in 1888 by Ordnance Survey, replacing the name Layne with Allen which is the old name for the lower reaches of the Camel.
[1] The other River Allen runs through Truro.
It springs northeast of Camelford and flows south-southwest through the Allen Valley passing St Teath and St Kew Highway to join the Camel near Sladesbridge.
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