A sixty-year unsolved mystery: Results from digging since 1989 confirm that there were in fact three periods of residents at Chengziya. To wit, during the neolithic age, from 4000-4600 years ago (the people of Lungshan culture); during the Hsia dynasty (called the Yueshi era in Shandong archaeological circles) after Lungshan; and then from the late Western Chou straight up to the Spring and Autumn (2800-2500 years ago).
從一九八九年後開始挖掘的結果證實，城子崖其實有三個時期的人住過：分別是距今四千到四千六百年前的新石器時代人類﹘﹘龍山文化人；晚於龍山的夏代人（山東考古學界稱為「岳石時期」，距今三千九百到三千年）；以及西周晚期一直延續到春秋晚期時人類（距今二千八百到二千五百年）。