Karakorum-Capital of the Mongol Empire

The Mongol Empire, once the world’s most formidable power, stretched from beyond Iran to the Pacific. Its capital from 1235 to 1260 AD was Karakorum,  47°12’26″N, 102°50’50″E a ruin stretching a kilometer from East to West and over four fifths of a mile from North to South. Today, the Buddhist fortified Erdene Zuu monastery, built in 1585 AD from the ruins of Karakorum, stands directly to the South of Karakorum. The walls of Karakorum are relatively easy to distinguish from Google Earth even with the direct lighting, especially after the help of this image. The roads and walls of Karakorum are outlined in the image below:

This was, perhaps, the largest city in Mongolia at the time of Ogedei. A model of it is located in the Ulaanbaatar museum, showing it to be a very much underpopulated place with a few religious structures and courtyards, two long, somewhat straight streets, and a yurt quarter (a further testament to the town’s lack of a large permanent population). It was destroyed in 1388 under the Ming Dynasty and was sparsely resettled later on. William of Rubruck, a Flemish monk, described the glories of Karakorum here (scroll down, not up, for the description). The capital was poor, practical, not too monumental, and insufficiently close to China, Mongolia’s most important (in Mongol rulers’ eyes) conquest, and, thus, had to be moved SE-ward to some more monumental ‘city’.
In 1260, the Mongol capital shifted to Xanadu, a recently-declared UNESCO world heritage site. Xanadu, a square over 1 1/3 mile in width, became the Mongol summer capital in 1271 and was abandoned after being destroyed by the Ming in 1369. Dadu/Bejing, another overly large rectangular capital, 5 1/5 miles N-S and 4 1/5 miles E-W, was established under Mongke as winter capital in the same year Xanadu became summer capital. This habit of Mongke of building enormous capitals reminds me of Sargon II’s Dur-Sharrukin, a 1 1/7 mile roughly-square compound and Nebuchadnezzar II’s 2 1/2 mile NW to SE incomplete attempt to build a massive rhomboidal wall around Babylon. Why powerful emperors with enormous accomplishments would wish to build enormous squarish capitals is beyond me.
Curiously enough, Ordu-Baliq/Kara-Balgasun, a ruin 24 kilometers to the Northeast of Karakorum and capital of the Ughyur khanate, seems to have been larger than Karakorum.