Karakorum was the capital of the Mongol Empire, built upon the great steppes and consisting of tents. In the 13th century, the Imperial Palace was built in Peking, which became the new capital. The Mongols living in Karakorum then dispersed, leaving the city abandoned.
In 1289, Noghai moved his army from Samarkand to Karakorum in preparation for an attack on Kublai Khan. (TV: Marco Polo)