Question: When did construction start on the great wall of china?
Disambiguated questions and answers: question: When did construction start on the first versions of the great wall of china?
When did construction start on most parts of the great wall of china visible today?
answer: 771–476 bc
Pre-imperial China
771 BC
1368–1644
Ming dynasty
Natural Questions answer: 771 -- 476 BC (from the Wikipedia article "History of the Great Wall of China")