Hebridean mythology and folklore

The Inner and Outer Hebrides off the western coast of Scotland are made up of a great number of large and small islands. These isolated and mostly uninhabited islands are the source of a number of Hebridean myths and legends. It is a part of Scotland which has always relied on the surrounding sea to sustain the small communities which have occupied parts of the islands for centuries, therefore, it is natural that these seas are a source for many of these legends.

Kelpies were said to occupy several lochs, including one at Leurbost.

The Blue men of the Minch (also known as storm kelpies), who occupy the stretch of water between Lewis and mainland Scotland, looking for sailors to drown and stricken boats to sink.

Seonaidh - a water-spirit who had to be offered ale.

It has been claimed that there is a mermaid's grave in Benbecula, but the exact location is unknown. The mermaid was killed in the early nineteenth century after having been seen for a couple of days, before a teenage boy threw a rock at it, killing the entity. Accounts stated that the upper part of the creature was the size of an infant, while the bottom was like a salmon.

Searrach Uisge - a monster who was said to occupy Loch Suainbhal. Resembling a capsized boat, this creature has been reported swimming around for one and a half centuries. Locals say lambs were once offered annually to the creature. Other such creatures have been reported in several other lochs, including Loch Urubhal.

At Loch Duvat in Eriskay, while out looking for a horse that escaped his farm in the mist, a farmer saw what he thought was his missing beast in the loch. As he approached, he realised he was looking at a strange creature which gave an unearthly yell, sending the farmer running home.

Various sea monsters have been reported off the shores of Lewis over the years, including a sighting reported in 1882 by a German ship off the Butt of Lewis. The ship, 15 kilometres off the coast, reported a sea serpent around 40 metres in length, with several bumps protruding from the water, along its back. Sea serpents have also been reported at the southern side of the island.

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Wikipedia