Kaiyuan Temple stands on the west side of Changsheng Street in Zhengding. Originally named Jingguan Temple, it was first built in the second year of the Xinghe reign of the Eastern Wei Dynasty (540 AD). It was renamed Jiehui Temple in the tenth year of the Kaihuang reign of the Sui Dynasty (591 AD), and received its current name by imperial edict in the twenty-sixth year of the Kaiyuan reign of the Tang Dynasty (738 AD). By the late Qing Dynasty, the temple fell into disrepair after years of neglect. All halls collapsed, leaving only the Bell Tower and Sumeru Pagoda standing.

The Bell Tower is a two-storey pavilion built of brick and wood, with a square floor plan. It has three bays in both width and depth, covering a construction area of 135 square meters. Topped with a single-eave hip-and-gable roof paved with grey tiles, the tower stands 14 meters tall. Its major wooden frames, column grid and bracket sets fully embody the architectural style of the Tang Dynasty, and quite a number of wooden components on the upper floor remain in their original Tang-dynasty form. It is the oldest surviving wooden bell tower in Hebei Province and also one of the earliest of its kind in northern China. Listed as a Major Historical and Cultural Site Protected at the National Level in 1988, it underwent a complete disassembly and restoration. A bronze bell hangs inside the tower. Standing 2.9 meters high with a mouth diameter of 1.56 meters and a wall thickness of 15 centimeters, the bell features an antique design and is a genuine relic of the Tang Dynasty.

Known locally as the Brick Pagoda or Square Pagoda, the Sumeru Pagoda is situated to the west of the Bell Tower. It rests on a square brick platform about 1.5 meters high. The pagoda itself is square-shaped with nine tiers of dense eaves, reaching a total height of 39.5 meters. The first storey is relatively tall, with a circle of steep stone slabs along its lower section. Powerful warrior relief sculptures are carved at both ends of each side. The entire structure above the stone waistline is built with blue bricks.

A stone arched gate is set on the front facade. The door frame is carved with vases and floral patterns, while the lintel bears a relief of Two Dragons Playing with a Pearl. A rectangular stone plaque is embedded above the lintel, inscribed with four large regular script characters: "Towering Sumeru". Each tier features brick corbelled eaves, with wind chimes hanging at the four corners. The pagoda gradually narrows from the second storey upwards. Slender, elegant and simple in style, it bears a strong resemblance to the Small Wild Goose Pagoda of the Tang Dynasty in Xi’an, and is a typical masterpiece of pagodas with corbelled eaves.

An octagonal wooden caisson ceiling was originally built on the upper part of the second storey, yet it has been damaged over time. The interior is now a hollow shaft with straight walls running through from top to bottom. Small square windows are installed on each of the eight storeys above the second floor, but no stairs are available for ascent.

The pagoda base, upturned lotus pedestal and inverted bowl of the spire are all brick-built, surrounded by gleaming bronze mirrors. On top stand a metal shaft and four precious pearls, making the spire look exceptionally lofty.

Local chronicles contain vague records about the pagoda’s construction date and cannot be fully trusted. Based on existing relics and historical documents, experts infer that it was initially erected in the tenth year of the Zhenguan reign of the Tang Dynasty (636 AD) and reconstructed in the fifth year of the Qianning reign (898 AD). Despite renovations in later dynasties, it still retains distinct architectural features of the Tang Dynasty.

As one of the Four Great Pagodas of ancient Zhengding, the Sumeru Pagoda is a precious treasure in China’s architectural heritage. It was designated a Provincial Key Cultural Relic Protection Unit in 1956 and elevated to the National level in 2006.

In June 2000, a massive broken stele base carved into the shape of a bixi (mythical tortoise) was unearthed on Fuqian Street in downtown Zhengding. Measuring 8.4 meters long, 3.2 meters wide and 2.6 meters high, it weighs 107 tons.

Preliminary research by experts confirms that it dates back to the Later Tang Dynasty, with a history of over 1,200 years. This remarkable discovery is of great significance for the study of history from the Later Tang to the Five Dynasties period. A rare artistic treasure across the country, it is hailed as the finest of its kind nationwide. The relic has now been relocated to Kaiyuan Temple for public viewing