Due to their banditry, cattle raiding and general lawlessness, the Clan Macgregor and all bearing the name, were outlawed by King James VI in 1603. The clan was dispersed and, while many adopted other names, those that still bore the name Macgregor were hunted and killed like animals. There is a local belief that the cave, which is really a cleft in the rocks high above the River Tummel at the east end of Dunalastair reservoir, was one of their hideouts during this time. It is rumoured that on one occasion, redcoat soldiers hunted down three members of the Macgregor clan to the cave and chased them onto the rocks in the river below where they were killed. The outlaw ban was only repealed in 1774. In Victorian times the cave was faked up as a summer house.