A king has a glass mountain built, declaring that whoever scales its slope could marry his daughter.

As the princess and her suitor climb, she slips; the glass mountain opens up and swallows her.

According to their notes, they found it in Frisian Archiv von Ehrentraut, written in Frisian dialect, which may have appealed to the Grimms because of its rustic nature, but which is difficult to read in German and more difficult to translate into English.

They harken back to Brynhildr's deliverance from the Hall of Flame, protected by a wall of shields atop Mount Hindarfjall, which only the horse Grani could reach.

Usually, the variants involve a princess sitting on top of the glass mountain, often holding a golden apple, to which knights on horseback must ascend.