Movies like The Ash Lad: In Search of the Golden Castle

Ash lad Espen, his father and half-bothers are delighted to be invited by prince Raul in a royal carriage to attend a grand ball for suitors of king Erik's daughter Kristin, but to their horror Pera and Pål are thrown in the dungeon, falsely accusing of poisoning the king. Espen sets out with princess Kristin on a long shot to find as cure the water of life in the mythical palace of Soria Moria, deep under an enchanted Norwegian lake, guarded jealously by its grim king's monsters. On the road they encounter robbers and fortune hunters, who cause problems, but ultimately find clues from the only man who ever returned from the lake, just in time for the execution of the alleged regicide culprits and inthronization of the real murderer unless they prevent it.