Halfdan the Black

Halfdan the Black (Old Norse: Halfdanr Svarti) (c.?810 – c.?860) was a ninth-century king of Vestfold. He belonged to the House of Yngling and was the father of Harald Fairhair, the first king of a unified Norway. 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 through ice weakened by cattle dung near a watering hole dug in the frozen lake. This structure in the Randsfjord reminds me of this story.