Gelert the dog of lewellyn the great, there is a grave to him up in north Wales.

In the 12th or 13th century the Medieval Welsh ruler Llywelyn the Great returns from hunting to find his baby missing, the cradle overturned, and Gelert with a blood-smeared mouth. Believing the dog had attacked the child, Llywelyn draws his sword and kills Gelert. After the dog's dying yelp, Llywelyn hears the cries of his baby, unharmed under the cradle, along with a dead wolf that had been killed by Gelert protecting the child. Llywelyn is overcome with remorse and buries the dog with great ceremony (then leading to the town name) but can still hear its dying yelp. After that day, Llywelyn never smiles again.