High above Glencoe is the hidden valley of Coire Gabhail, more commonly known as the Lost Valley where the surviving Macdonalds fled to after they were set upon by the Campbells in the infamous Glencoe massacre of 1692. The Macdonalds had used the flat wide valley to squirrel away cattle they had raided from other clans. The name Coire Gabhail means the corrie of the bounty, a corrie being the head of a valley.
It is considered the valley was formed when, sometime in pre-history, a giant landslip blocked the valley creating a loch which, over the millennia, eventually silted up. The mossy talus of the landslip with its tangle of birch trees creates a difficult enough approach for humans let alone cattle.