Madoc ap Uthyr

In early Arthurian literature, Madoc ap Uthyr (also known as Madawg) is the son of Uther Pendragon, brother to Arthur and father of Eliwlod. He is memorialized with The Death Song of Madawg (Marwnad Madawg) from the Book of Taliesin which laments his death at Erof's hands, and is also mentioned in the poem Arthur and the Eagle.

A Madawg's grave is mentioned in Englynion y Beddau, which states:

Whose is the quadrangular grave With its four stones around the front? The grave of Madawg the intrepid warrior.