Halvdanshaugen
Heimskringla, Fagrskinna, Ágrip and Historia Norwegiæ all relate that Halfdan drowned when he fell through the ice at the inlet Røykenvik in the lake Randsfjorden on his return home from Hadeland. His horse and sleigh broke though ice weakened by cattle dung near a watering hole dug in the frozen lake. He was buried in a mound at Stein in Ringerike.
Heimskringlas narrative adds that each of the districts of his kingdom wanted to claim his grave, and that it was agreed to divide his body into four pieces so each district could bury a piece of it, resulting in four different site called Halvdanshaugen (from the Old Norse word haugr meaning mound). According to this version, only his head is buried in Ringerike.
Read more about this topic: Halfdan The Black