; ▁at ▁a ▁minimum , ▁the ▁era ▁tradition ally ▁denoted ▁as ▁the ▁X ia ▁dynast y ▁marked ▁an ▁evolution ary ▁stage ▁between ▁the ▁late ▁Ne ol ith ic ▁cult ures ▁and ▁the ▁urban ▁civil ization ▁of ▁the ▁Shang ▁dynast y . ▁ ▁In ▁ 2 0 1 1 , ▁Chinese ▁arch ae olog ists ▁un cover ed ▁the ▁remains ▁of ▁an ▁imperial ▁s ized ▁palace — dated ▁to ▁about ▁ 1 7 0 0 ▁BC — at ▁Er lit ou ▁in ▁Hen an , ▁further ▁fuel ing ▁the ▁discuss ions ▁about ▁the ▁existence ▁of ▁the ▁dynast y . ▁ ▁Arch ae ological ▁evidence ▁of ▁a ▁large ▁out bur st ▁flo od ▁that ▁destroyed ▁the ▁La j ia ▁site ▁on ▁the ▁upper ▁reaches ▁of ▁the ▁Y ellow ▁River ▁has ▁been ▁dated ▁to ▁about ▁ 1 9 2 0 ▁BC . ▁This ▁date ▁is ▁shortly ▁before ▁the ▁rise ▁of ▁the ▁Er lit ou ▁culture ▁in ▁the ▁middle ▁Y ellow ▁River ▁valley ▁and ▁the ▁Y ues hi ▁culture ▁in ▁Sh and ong , ▁following ▁the ▁decl ine ▁of ▁the ▁Long sh an ▁culture ▁in ▁the ▁North ▁China ▁P lain . ▁The ▁authors ▁suggest ▁that ▁this ▁flo od ▁may ▁have ▁been ▁the ▁basis ▁for ▁the ▁later ▁myth , ▁and ▁contributed ▁to ▁the ▁transition ▁of ▁cult ures . ▁They ▁further ▁argue ▁that ▁the ▁timing ▁is ▁further ▁evidence ▁for ▁the ▁identification ▁of ▁the ▁X ia ▁with ▁the ▁Er lit ou ▁culture . ▁However , ▁no ▁evidence ▁of ▁contempor aneous ▁w ides p read ▁flo oding ▁in ▁the ▁North ▁China