Suzhou City was an important stronghold of the State of Wu in the Spring and Autumn Period. At that time, He Lv ordered Wu Zixu to build a city. After the completion of the project, the King of Wu was overjoyed and named it "the city of Helv", and the ministers held a big banquet to celebrate. Only Wu Zixu was unhappy. Wu Zixu predicted that if the king of Wu was arrogant and did not guard against Gou Jian and Fan Li, the king of Yue, the country would perish sooner or later.
After returning to the camp, he secretly told his entourage: "After my death, if the country is in trouble and the people are hungry and cold, you can dig three feet under Xiangmen (the gate of Suzhou at that time) to get food."
As expected, Wu Zixu was later framed and killed, and Wu was wiped out by the Vietnamese army. At this time, the capital ran out of food, and Wu Zixu's followers thought of Wu Zixu's instructions before his death, so they led the people to Xiangmen to tear down the city and dig the ground, only to find that the bricks of Xiangmen were not made of clay, but made of glutinous rice ground into powder.
In order to commemorate and remember Wu Zixu's achievements and loyalty, later generations formed the habit of eating rice cakes to remember Wu Zixu.