Legend has it that the Cailleach was tired from a long day herding deer. Atop Ben Cruachan she fell asleep on her watch and a well she was tending overflowed, running down from the highlands and flooding the valleys below, forming first a river and then the loch. The overflowing well is a common motif in local Gaelic creation tales - as seen in the goddess Boann's similar creation of the River Boyne in Ireland. Other connections to the region include her above-mentioned strong ties with the fierce whirlpool in the Gulf of Corryvreckan.