Introduction to Cai Zichi: Cai Zichi is about ten acres in size and is rectangular in shape. According to legend, it was opened by Cai Lun when he returned to his hometown from the palace to spread papermaking. It was used to wash plant fibers and has a history of more than 1,800 years. Sihou Pavilion was built in the middle section of the pool. If you walk on the stone bridge on a moonlit night, you can see the twin moons competing for their glory. In the rippling pool, there are chants of "Only Cai Chi is beautiful with the twin moons".