Khara-Khoto (Mongolian: Khar Khot "black city") was a Tangut city in the Ejin Banner of Alxa League in western Inner Mongolia near Juyan Lake Basin. It has been identified as the city of Etzina, which appears in The Travels of Marco Polo. The present banner Ejin Banner is named after this city.
The city was founded in 1032 and became a thriving center of Western Xia trade in the 11th century. There are remains of 30-foot (9.1 m)-high ramparts and 12-foot (3.7 m)-thick outer walls. The outer walls ran for some 421 m (1,381 ft) east-west by 374 m (1,227 ft) north-south.
The walled fortress was first taken by Genghis Khan in 1226, but—contrary to a widely circulated misunderstanding—the city continued to flourish under Mongol overlordship. During Kublai Khan's time, the city was expanded, reaching a size three times bigger than during the Tangut Empire.