Meanwhile, on the 17th of March, King Francis had been set at liberty. Charles in a letter to his brother says: 'The King of France was restored to his kingdom on the 17th of this month (February), on my receiving the Dauphin and Duke of Orleans as hostages, whom I have desired to be taken to Burgos; and the said King of France promises to accomplish all that he has engaged in by the treaty of peace....' Guicciardini gives the following interesting account of the exchange of prisoners at Fuenterrabia: 'By this time the French king was come to Fuenterrabia, a town appertaining to the emperor, standing near the Ocean Sea upon the frontiers of Biscay and the duchy of Guyenne; and on the other side the Lady Regent was arrived with the children of France at Bayonne, which is not far from Fuenterrabia.... Then the 18th day of March, the French king, accompanied by the viceroy, Captain Alarçon, with fifty horse, came to the shore of the river that divideth the realm of France from the kingdom of Spain; at the same time M. de Lautrech, with the king's children, and the like number of horse, presenting themselves on the other side. There was in the midst of the river a great barque made fast with anchors, in which was no person. The king approached to this barque in a little boat, wherein he was accompanied by the viceroy, etc.... all armed with short weapons, and on the other side of the barque were likewise brought in a little boat, M. de Lautrech, with the hostages... after this the viceroy went into the barque... and the king with him.... M. de Lautrech fetched out of the boat into the barque the Dauphin, who being given to the viceroy... was forthwith bestowed in his boat, and after him followed the little Duke of Orleans, who was no sooner entered the barque than the French king leaped out of the barque into his boat with such swiftness that his permutation was thought to be done at one self instant, and then the king being brought to the shore, mounted suddenly (as though he had feared some ambush) upon a Turkish horse of a wonderful swiftness, which was prepared for the purpose, and ran without stay to St. John de Luz, a town of his obedience, four leagues from thence; and being there readily relieved with a fresh horse, he ran with the same swiftness to Bayonne, where he was received with incredible joy of all the Court.'[122] [122] Published in 1618. Mentioned by W. Bradford in his _Correspondence of the Emperor Charles V._ In a despatch to the emperor, written on March 23rd, Ochoa de Ysasaga announced that 'The day that the King of France was released from his captivity he leaped from the boat, with water up to his knees, mounted a horse that had been prepared for him, and rode without stopping to St. Jean de Luz, where he dined, and was visited by the flower of the French nobility, who came to congratulate him.[123] [123] _Calendar of Spanish State Papers_, vol. iii.