8: 00 a.m. to 8: 00 p.m. 10. The activity center for retired military cadres is mainly responsible for organizing cultural and sports activities, major festivals and commemorative activities, and learning and training activities for retired military cadres in the city. As of September 17, 2022, the opening hours of the activity center are from 8: 00 a.m. to 8: 00 p.m. 10. Shanghai, also called "Shanghai" for short, is the largest economic center and an important international financial center city in China, and it is the first batch of coastal open cities.