Jinchuan Mine Park, one of the largest man-made tiankeng in China, was shocked here, and it was artificially excavated such a large pit on the body of the earth. This Jinchuan open-pit nickel pit has left an oval artificial tiankeng with a length of 1,300 meters, a width of 700 meters and a depth of more than 310 meters. I am not sure if it is the largest artificial tiankeng in China, but I know There is indeed such a saying.