From an article in Uig News by Dave Roberts.
It appears that shielings were constructed so that one airigh could easily be seen from another, but it is said that very often the girls from a number of shielings would sleep in one building for company. The ancient shieling grounds for Brenish, Islivig and Mangersta were way beyond Raonasgail valley, in the moors north of Loch Craobhaig, at Fidigidh. The people of Carnish had their shielings by Loch Raonasgail, and at Ceann Chuisil. There are also ruins of old shieling structures closer to home, west of Mealisval, Cracaval and Laival. In the late nineteenth, and into the twentieth century, shieling activity was largely restricted to these closer locations.
About half a mile from Tealasdale is one of the shieling grounds of Old Mangersta, situated north of Ron Beag and west of Loch Faorbh. At the west end of Tealasdale is Sgorr Reamher and Bealach nan Imrich – “the pass of the flitting”, and below the Sgorr is the ruin of a very large and well built airigh. It is marked clearly on the first edition ordnance survey map. Its location is not very inviting. It is sheltered from the easterly winds but not from the southwesterlies. Even in summer the sun does not reach it until well into the day. This is Airigh na h’Aon Oidhche – “the one night shieling”.
The story of this shieling is vague and only partially recalled. However, something must have occurred the very first night because since then everyone has shunned it. The ruin stands there to this day abandoned and forlorn. Just around the corner is a cliff which in high winds is reputed to make loud and frightening noises. In the memory of an impressionable young woman there would have been all the tigh ceilidh stories of sheep stealing and murdering old ladies, of water horses and mischievous fairies. She would also have heard the story about the girl from Baile na Cille who had been out at the southern end of Loch Suaineabhal, when a monster had come out of the loch. It consumed a stirk, but before it could attack her she ran all the way back home to tell of the terrible event. A bowman from Great Bernera was sent for and he dispatched this particular creature, but no doubt other lochs contained similar beasts.
Anyway, it is probable that the girl from Mangersta, on her first night at the shieling, did not having a good night, in unfamiliar surroundings and amid strange sounds. Awakened by the strange sounds of the wind, she thought she saw a deer hound – or perhaps something worse – and after a terrifying night, as soon as it was light enough, she left the shieling and ran home wildly still afraid that the dog would reappear and pursue her. When she got back she was in a terrible state and was adamant that she would never spend another night in that haunted building. It would seem that the veracity of her story was not doubted because to this day, no one else has dared to sleep in the shieling for fear that the black beast will return.
(Dave Roberts with help from people of Brenish and Islivig)