Aideen's Grave, Howth, County Dublin.

Aideen was the daughter of Aonghus, who lived at Binn Edair. Her husband was killed in battle around 284 and she died of grief and was buried there. While she may have been buried there, the portal tomb, with its 35 tonne capstone is at least two thousand years older than this. The peninsula later became known as Howth after the name was adopted by the Normans.