Introduction to Kaiyuan Tieniu: Each Tang Kaiyuan Tieniu statue is about 1.9 meters high, 3 meters long and 1.3 meters wide. There is a horizontal axis behind the tail of the ox, with a diameter of about 0.4 meters and a length of about 2.3 meters. There are patterns on the head of the shaft, and each shaft is different, including beads, rhombus, curly grass, lotus, etc. The iron ox has a vivid shape, with its front legs in a pedaling shape and its hind legs in a crouching shape. Its horns are straightened and its head is raised. The body of the ox is strong and strong. An iron shaft is attached to the tail to tie the pontoon bridge. There is a mountain under the belly, and six iron pillars with a diameter of 0.4 meters and a length of about 3.6 meters are connected diagonally forward. Each iron pillar has an iron foot extending in the opposite direction, and its function is the same as a ground anchor. There are traces of mold seams on the upper and lower parts of the iron bull. Traces of casting and mold blocks can be observed and the casting technology can be analyzed.