The salmon is also connected mythologically to the Celtic Otherworld and the tales of the Sidhe. Symbolically it can exist in two worlds, one being the freshwater rivers and also in the otherworld being in the saltwater of the sea. There is a story mentioned in the Annal of the four Masters about Tuan mac Cairill, who is said to have lived during the age of the Patholónians. He had the supernatural ability to shape-shift into different forms of creature, the final form being a salmon, just before being eaten by the wife of a chieftain called Cairill, who later gave birth to him as human once again. He lived for several thousand years in numerous different reincarnations as animals and seen through their eyes the coming of the different ages and invaders throughout Irish history, right up to the dawning of the Christian age. He was known as the ‘seer’ or the storehouse of knowledge of Irish history. Fintan mac Bóchra also transformed into a salmon in a place now known as Fintan's Grave near Lough Derg, he arrived with the first settlers in Ireland, the Cessairians.