Highlights: Like the four-leaf clover, for Europeans, clay/pottery products are also auspicious things that can bring luck. The mountain of pottery in Rome (in the ancient Roman language, Testaccio means clay) is actually made of pottery products more than a thousand years ago. It used to be a trading market in ancient Rome. At that time, food, oil and wine were of course not in plastic bags, but in oval earthen pots with narrow necks or other earthenware containers, and then passed through the Tiber River. Wade all the way to Rome. The useless pots were thrown aside. By the end of the 4th century AD, the pottery piece mountain was basically formed. At present, the pottery piece mountain has a circumference of about 1 km and a height of 45 meters. The older pottery vessels on the mountain came from Baetica in ancient Rome and were mainly used to hold olive oil. Manufacturers' stamps and other markers can also be identified on these pottery vessels, allowing archaeologists and sociologists to analyze the economic details of ancient Rome at the time. It is estimated that the mountain of pottery pieces was made of 53 million pots.