Huqiu Pagoda, also known as the Yunyan Temple Pagoda, was built in the ninth year of Renshou (601), Emperor Wendi of the Sui Dynasty. It was first built into a wooden pagoda and then destroyed. The existing Huqiu Pagoda was built in the eighth year of Ganyou in the latter Zhou Dynasty to the second year of Jianlong in the Song Dynasty (959-961). The tower system is planar octagonal, grade seven. The original top of the tower was destroyed by lightning. When it was rebuilt in 1956, a large number of precious cultural relics such as stone letters, sutras, bronze Buddhas, bronze mirrors and lotus bowls of Yue kiln celadon were found in the third layer. The Huqiu Pagoda is 47.5 meters high. Its body is made of bricks and weighs more than 6,000 tons. According to records, due to foundation reasons, since the Ming Dynasty (1368-1644), the Huqiu Tower tilted northwest. The center of the top of the tower deviated from the bottom center by 2.3 meters, which is known as the "Leaning Tower of Oriental Pisa". In 1956, the Suzhou Municipal Government invited experts in ancient architecture to adopt iron hoop grouting to reinforce and renovate the pagoda. Finally, the pagoda was preserved. In 1961, it was listed as one of the key cultural relics protection units in China.