This ruined Tangut city was built in 1032 and captured by Genghis Khan in 1226 (his last great battle). Khara Khoto continued to thrive under Mongol occupation, but in 1372 an upstart Ming battalion starved the city of its water source, killing everyone inside. Six hundred years of dust storms nearly buried Khara Khoto, until the Russian explorer PK Kozlov excavated and mapped the site, recovering hundreds of Tangut-era texts (now kept at the Institute of Oriental Manuscripts in St Petersburg).
Located about 25km southeast of Ejina Qi, the allure here is the remoteness of the site and surrounding natural beauty. A great time to visit is late September to early October when the poplar trees are changing colours; but be warned that every hotel room in Ejina Qí will be booked out at this time.