"Xi 'ai Office" is one of the organizations that China launched underground struggle in Xi during the late liberation war of War of Resistance against Japanese Aggression. /kloc-in the winter of 0/939, Chao, who worked in the eighth route army security office, was ordered to go underground to carry out intelligence work. In order to carry out our work and protect ourselves, 1943, Chao raised funds to buy Room 7 in Lianhuachi Street, Dalian, and connected Room 7 in Lianhuachi Street, Room 24 in Wang Jiaxiang, Room 24 in A and Room 25 in Sichuan, and built a secret studio. This secret studio is 5.7 meters above the ground and has two caves for sending and receiving telegrams and printing documents. There is a passage between the two caves. The passage can only be passed by one person, and even important parts need to crawl. The entrance to the cave is equipped with a kite turnover device, and the hole is covered with 3-inch thick elm bark. In case of emergency, the elm is covered with bluestone, so that water and toxic gases cannot enter. The basement has antenna equipment leading to the ground, skylight equipment for adjusting air, drying equipment for protecting the machine from moisture, safety equipment for storing passwords and confidential documents, and two wells, one bright and one dark, for transmitting messages, contacting the ground, transporting food, destroying documents and providing defecation. The underground studio has five entrances and exits, connecting four courtyards on the ground.