Chingiz-Khan and his sons had no no capital in Khitai, as has been mentioned in every history, but because Möngke Qa'an had given that kingdom to Qubilai Qa'an, and he with a farsighted view had seen in it an exceedingly prosperious kingdom with many important provinces and countries adjacent to it, he had chosen it [as the site of] his capital. He established his summer residence in the town of Khan-Baliq, which is in Khitayan called Jungdu and which had been one of the capitals of the rulers of Khitai.
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As it had been destroyed by Chingiz-Khan, Qubilai Qa'an wished to rebuild it, and for his own fame and renown he built another town called Daidu alongside it and so that they adjoin each other.