Under the Sui, Cao Prefecture included Yuanqu County. The administrative region of Caozhou in the Tang dynasty is in the border region of modern southwestern Shandong and eastern Henan. It probably includes parts of modern:

• Under the administration of Heze, Shandong:
  • Heze
  • Cao County
  • Dingtao County
  • Chengwu County
  • Dongming County
• Under the administration of Shangqiu, Henan:
  • Minquan County

• Shi Weile, ed. (2005). Zhongguo Lishi Diming Da Cidian (中国历史地名大词典) [Large Dictionary of Chinese Historical Place Names] (in Chinese). China Social Sciences Press. p. 2326. ISBN 7-5004-4929-1.