After travelling for a long time, the young man came at last to the palace of the king whose daughter he wished to marry. When he saw the palace, he was exceedingly sad, and remembered the words of the princess; for, after all his wanderings and sufferings, he had learnt no trade, and had never been able to find what trade it was "that no one knows." Whilst considering what he had better do, he suddenly recollected the halter, the key, and the iron chain, which he had carried concealed about him ever since he left the castle of the four giants. He then said to himself, "Let me see what these things can do!" So he took the halter and struck the earth with it, and immediately a handsome horse, beautifully caparisoned, stood before him. Then he struck the ground with the iron chain, and instantly a hare and a greyhound appeared, and the hare began to run quickly and the greyhound to follow her. In a moment the young man hardly knew himself, for he found himself in a fine hunting-dress, riding on the horse after the hare, which took a path that passed immediately under the windows of the king's palace.

Now, it happened that the king stood at a window looking out, and noticed at once the beautiful greyhound which was chasing the hare, and the very handsome horse which a huntsman in a splendid dress was mounted on. The king was so pleased with the appearance of the horse and the greyhound, that he called instantly some of his servants, and, sending them after the strange rider, bade them invite him to come to the palace. The young man, however, hearing some people coming behind him calling and shouting, rode quickly behind a thick bush, and shook a little the halter and the iron chain. In a moment the horse, the greyhound, and the hare had vanished, and he found himself sitting on the ground under the trees dressed in his old shabby clothes. By this time the king's servants had come up, and, seeing him sitting there, they asked him whether he had seen a fine huntsman on a beautiful horse pass that way. But he answered them rudely, "No! I have not seen anyone pass, neither do I care to look to see who passes!"

Then the king's servants went on and searched the forest, calling and shouting as loudly as they could, but it was all in vain; they could neither see nor hear anything of the hunter. At length they went back to the king, and told him that the horse the huntsman rode was so exceedingly quick that they could not hear anything of him in the forest.

The young man now resolved to go to the hut where his old parents lived; and they were glad to see that he had come back to them once more.

Next morning, the son said to his father, "Now, father, I will show you what I have learned. I will change myself into a beautiful horse, and you must lead me into the city and sell me, but be very careful not to give away the halter, or else I shall remain always a horse!" Accordingly, in a moment he changed himself into a horse of extraordinary beauty, and the father took him to the market-place to sell him. Very soon a great number of people gathered round the horses wondering at his unusual beauty, and very high prices were offered for him; the old man, however, raised the price higher and higher at every offer.

The news spread quickly about the city that a wonderfully handsome horse was for sale in the market-place, and at length the king himself heard of it, and sent some servants to bring the horse, that he might see it. The old man led the horse at once before the palace, and the king, after looking at it for some time with great admiration, could not help exclaiming, "By my word, though I am a king, I never yet saw, much less rode, so handsome a horse!" Then he asked the old man if he would sell it him. "I will sell it to your Majesty, very willingly," said the old man; "but I will sell only the horse, and not the halter." Thereupon the king laughed, saying, "What should I want with your dirty halter? For such a horse I will have a halter of gold made!" So the horse was sold to the king for a very high price, and the old man returned home with the money.

Next morning, however, there was a great stir and much consternation in the royal stables, for the beautiful horse had vanished somehow during the night. And at the time when the horse disappeared, the young man returned to his parents' hut.

A day or two afterwards the young man said to his father, "Now I will turn myself into a fine church not far from the king's palace, and if the king wishes to buy it you may sell it him, only be sure not to part with the key or else I must remain always a church!"

When the king got up that morning and went to his window to look out, he saw a beautiful church which he had never noticed before. Then he sent his servants out to see what it was, and soon after they came back saying, that "the church belonged to an old pilgrim, who told them that he was willing to sell it if the king wished to buy it." Then the king sent to ask what price he would sell it for, and the pilgrim replied, "It is worth a great deal of money".

Whilst the servants were bargaining with the father an old woman came up. Now this was the same old woman who had sent the young man to the castle of the four giants, and she herself had been there and had learnt the trade that no one knew. As she understood at once all about the church, and had no mind to have a rival in the trade, she resolved to put an end to the young man. For this purpose she began to outbid the king, and offered, at last, so very large a sum of ready money, that the old man was quite astonished and confused at seeing the money which she showed him. He accordingly accepted her offer, but whilst he was counting the money, quite forgot about the key. Before long, however, he recollected what his son had said, and then, fearing some mischief, he ran after the old woman and demanded the key back. But the old woman could not be persuaded to give back the key, and said it belonged to the church which she had bought and paid for. Seeing she would not give up the key, the old man grew more and more alarmed, lest some ill should befall his son, so he took hold of the old woman by the neck and forced her to drop the key. She struggled very hard to get it back again, and, whilst the old man and she wrestled together, the key changed itself suddenly into a dove and flew away high in the air over the palace gardens.

When the old woman saw this, she changed herself into a hawk and chased the dove. Just, however, as the hawk was about to pounce upon it, the dove turned itself into a beautiful bouquet, and dropped down into the hand of the king's daughter who happened to be walking in the garden. Then the hawk changed again into the old woman, who went to the gate of the palace and begged very hard that the princess would give her that bouquet, or, at least, one single flower from it.

But the princess said, "No! not for anything in the world. These flowers fell to me from heaven!" The old woman, however, was determined to get one flower from the bouquet, so, seeing the princess would not hear her, she went straight to the king, and begged piteously that he would order his daughter to give her one of the flowers from her bouquet. The king, thinking the old woman wanted one of the flowers to cure some disease, called his daughter to him, and told her to give one to the beggar.

But just as the king said this, the bouquet changed itself into a heap of millet-seed and scattered itself all over the ground. Then the old woman quickly changed herself into a hen and chickens, and began greedily to pick up the seeds. Suddenly, however, the millet vanished, and in its place appeared a fox, which sprang on the hen and killed her.

Then the fox changed into the young man, who explained to the astonished king and princess that he it was who had demanded the hand of the princess, and that, in order to obtain it, he had wandered all over the world in search of someone who could teach him "the trade that no one knows".

When the king and his daughter heard this, they gladly fulfilled their part of the bargain, seeing how well the young man had fulfilled his.

Then, shortly afterwards, the king's daughter married the son of the poor old couple; and the king built for the princess and her husband a palace close to his own. There they lived long and had plenty of children, and people say that some of their descendants are living at present, and that these go constantly to pray in the church, which is always open because the key of it turned itself into a young man who married the king's daughter after he had shown to her that he had done as she wished, and learnt, for her sake, "the trade that no one knows".