Luding Bridge, also known as the Iron Cable Bridge, is located on the Dadu River in Luding County, Sichuan Province. After the Kangxi emperor unified China, the bridge was built by the Royal approval to strengthen cultural and economic exchanges in Sichuan-Tibet areas, and the bridge was erected. The bridge, built in 1705 and built in 1706, is a masterpiece of ancient bridge architecture in China and is the first major national cultural relics protection unit announced by the State Council. Luding Bridge is 103 meters long and 3 meters wide. 13 iron chains are fixed in the bridge platforms on both sides of the bank, 9 as bottom chains, 4 as handrails on both sides, a total of 12,164 iron rings are interlocked, and the iron parts of the bridge weigh more than 40 tons. The bridgehead castle on both sides of the Luding Bridge is an ancient building of Han wooden structure, unique to China. Since Qing Dynasty, Luding Bridge has been an important passageway and military mainstay for Sichuan to Tibet. On May 29, 1935, the Long March of the Red Army of China passed through here, with 22 warriors as the lead commando team, braved the enemy's gunfire, and advanced on the iron cable bridge, killing the bridge head guard at one stroke. "Flying the Luding Bridge" opened the passage of the Red Army Long March to the north to resist Japan, and wrote the war miracle of "thrilling, dangerous, strange and insane" in the history of the Chinese revolution and the history of the world military.