Táin Bó Cúailnge
In the "Táin Bó Cúailnge", Cúchulainn fights Lethan at Ath Carpat ("chariot ford") on the river Níth. This takes its name from the Irish "níth", meaning "combat". The modern name Dee derives from the town of Ardee ("Baile Átha Fhirdhia", "town of Ferdiad's ford").