Bell Tower, Drum Tower is known as "Sister Tower", "Wenwu Tower", both of which were built in the Ming Dynasty, and have a history of more than 620 years. The so-called morning bell and evening drum tower, which faces the bell tower in the west, was built in the thirteenth year of Zhu Yuanzhang Hongwu, the emperor of the Ming Dynasty. It was built four years earlier than the bell tower. It was rebuilt twice in the thirty-eighth year of Kangxi in the Qing Dynasty and in the fifth year of Qianlong in the Qing Dynasty. Upstairs, the original side of the huge drum is called "Drum Tower" because it beats drums every day. After years of vicissitudes, now the giant drum has long disappeared, but the Yugu Tower stands tall. Antique performance "morning bell and evening drum" - "Since 2007, Xi'an bell and drum tower began to hold antique performance activities "morning bell and evening drum". Every day, at 9 am, 12 noon and 3 p.m., Jingyun bell on Xi'an bell tower rings 24 times respectively; at 6 p.m., the 24 solar terms on the drum tower first ring in unison, and then the drum sounds 24 times to announce the evening. This marked the restoration of Xi'an's "morning bell, evening drum" timekeeping system, which had disappeared for more than 100 years.