A Western Han dynasty ancient tomb group was accidentally found at a construction site in Puyang city, China's Henan province, on April 10. After a period of protective excavation of the tomb group, archaeologists found more than 230 ancient tombs in all, and a total of more than 600 cultural relics have been unearthed so far. During the excavation, archaeologists discovered an airtight copper pot covered in rust. They found the pot had a liquid weighing about half a kilogram in it.