"You, rider of the black horse, make that," said Prince Underwaves, "before the morrow's sun rises." The lad went out to the horse and leaned his elbow on his neck and sighed, thinking that this castle never could be made for ever. "There never came a turn in my road yet that is easier for me to pass than this," said the black horse. Glance that the lad gave from him he saw all that there were, and ever so many wrights and stone masons at work, and the castle was ready before the sun rose. He shouted at the Prince Underwaves, and he saw the castle. He tried to pluck out his eye, thinking that it was a false sight. "Son of King Underwaves," said the rider of the black horse, "don't think that you have a false sight; this is a true sight." "That's true," said the prince. "You are a son of success, but I am a son of success too. There will be no more mistakes and delays, but a wedding now." "No," said she. "The time is come. Should we not go to look at the castle? There's time enough to get married before the night comes." They went to the castle and the castle was without a "but"---- "I see one," said the prince. "One want at least to be made good. A well to be made inside, so that water may not be far to fetch when there is a feast or a wedding in the castle." "That won't be long undone," said the rider of the black horse. The well was made, and it was seven fathoms deep and two or three fathoms wide, and they looked at the well on the way to the wedding. "It is very well made," said she, "but for one little fault yonder." "Where is it?" said Prince Underwaves. "There," said she. He bent him down to look. She came out, and she put her two hands at his back, and cast him in. "Be thou there," said she. "If I go to be married, thou art not the man; but the man who did each exploit that has been done, and, if he chooses, him will I have." Away she went with the rider of the little black horse to the wedding. And at the end of three years after that so it was that he first remembered the black horse or where he left him. He got up and went out, and he was very sorry for his neglect of the black horse. He found him just where he left him. "Good luck to you, gentleman," said the horse. "You seem as if you had got something that you like better than me." "I have not got that, and I won't; but it came over me to forget you," said he. "I don't mind," said the horse, "it will make no difference. Raise your sword and smite off my head." "Fortune will now allow that I should do that," said he. "Do it instantly, or I will do it to you," said the horse. So the lad drew his sword and smote off the horse's head; then he lifted his two palms and uttered a doleful cry. What should he hear behind him but "All hail, my brother-in-law." He looked behind him, and there was the finest man he ever set eyes upon. "What set you weeping for the black horse?" said he.