Gráinne was the daughter of King Cormac, the most lauded of all high kings. Betrothed to Fionn MacCumhaill (Finn McCool), she eloped with Diarmuid, one of the king's warriors, on her wedding night. This became the subject of the epic The Pursuit of Diarmuid and Gráinne. Gráinne's Fort and the northern and southern Sloping Trenches to the northwest are burial mounds.