"Greta" derives from the Old Norse "Griótá", meaning "stony stream".

[1] The name is in records dating from the early 13th century, and also appears in Latinised form, as "Gretagila", at the time of Magna Carta.

[2] The medieval bridge over the river in Keswick was unusual in having two arches; on the great coach road from Kendal to Cockermouth all but two of the other bridges (Troutbeck and Portinscale) crossed their rivers in a single span.

The current Greta Bridge in Keswick is another two-arch structure, built in 1926.

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