Linn (geology)
In Scotland and northern England a Linn is a geographical water feature.  

In Scotland it describes where a watercourse has cut through a shelf of hard rock creating a narrow (usually), steep-sided cut though which the watercourse runs.

Typically there is only one named Linn on any watercourse - although obviously - there may actually be more than one feature with the necessary attributes.

The photograph of the Linn of Dee illustrates the attributes of a typical 'Linn'.

In Gordon (1925) the author describing a walk down Glen Avon in the Cairngorms mentions two Linns on the River Avon - first:

A linn may also refer to a waterfall or a pool at the foot of a waterfall, with the derivation a confusion of Scots Gaelic linne (pool) and Old English  (torrent).

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