Introduction to the open-pit mining area: The appearance of the old open-pit mining site resembles the Colosseum. It is a giant hole left by the open-pit mining in the past. With cascading slopes and strange terrain, it is a characteristic landscape left by modern industry. The Baoshan open pit mine was mined in 1966 and closed in 1995. A total of 5.88 million tons of ore was mined, with an output value of 450 million yuan (constant price in 90 years). The metals mined are mainly copper, molybdenum, bismuth, and sulfur. After 30 years of mining, a huge upward pot has been formed. The upper part is 550 meters long and 500 meters wide. The lower part is 98 meters long and 35 meters wide. There are a total of 24 steps, each step is 10 meters high, and the center vertical height reaches 220 meters. . This scale is extremely rare among nonferrous metal mines in the country.