Scáthach

The Tochmarc Emire tells how Cú Chulainn journeys to Alba (Scotland) to train with Scáthach at Dún Scáith, her Fortress of Shadows on the Isle of Skye. To reach it he must cross the Bridge of Leaps — a bridge that buckles at its midpoint when anyone steps on an end; only the most perfectly timed leap from the far bank can land a warrior safely. Once inside, Cú Chulainn trains alongside his companion Ferdiad in the most advanced combat arts of the mythological world: the salmon leap, the feat of the chariot-wheel, and the arts of underwater fighting. Scáthach accepts only those already exceptionally brave; the school's sole criterion is demonstrated courage.

Scáthach bestows on Cú Chulainn her most fearsome weapon: the Gáe Bulg, a javelin thrown with the foot that opens into thirty barbs on entering the body and cannot be removed without cutting away all the surrounding flesh. She also gives him a prophecy of the battles ahead, seeing his fate with the clear eye of a seeress. Before he departs, Cú Chulainn fights Scáthach's twin sister and rival Aife — described in the text as the most dangerous warrior in the world — and defeats her. The encounter produces a son, Connla, whose tragic death later at Cú Chulainn's unknowing hand is one of the great sorrows of the Ulster Cycle.

The primary source is Tochmarc Emire, a foretale to the great Táin Bó Cúailnge that survives in the twelfth-century Book of the Dun Cow (Lebor na hUidre) and other manuscripts. Scáthach is culturally exceptional: a female teacher whose authority over the most dangerous men in mythology is entirely unchallenged. She is not a goddess but a semi-divine mortal of extraordinary skill, and her prophecy-gift places her in a tradition of warrior-seers who straddle combat and foresight. The ruins called Dun Sgathaich near Tokavaig on the Sleat Peninsula, built in the fourteenth century, mark where the mythological fortress was anchored in the landscape of Skye.