In the north of Di'anmen in Beijing, south of the Bell and Drum Towers, on the former Jade River channel east of the front sea of Shichahai, there is an ancient stone bridge called Wanning Bridge. Because Di'anmen is the back gate of the imperial city, the common people also call this bridge the back gate bridge or Di'anmen Bridge. This ancient stone arch bridge, which has experienced vicissitudes, was built in the 22nd year of the Yuan Dynasty (1276) during the reign of Emperor Shizu of Yuan. It was originally a wooden bridge, but later rebuilt as a stone bridge. It is one of the heritage sites of the Grand Canal World Cultural Heritage in Beijing.
Because of its location east of Shichahai, Wanning Bridge was also called Haizi Bridge in the Yuan Dynasty. "Xijin Zhi Ji Yi" records that Wanning Bridge "is located east of Xuanwu Lake, named Chengqing Sluice. It was built in the middle of the Yuan Dynasty, east of Haizi. It was rebuilt with stone after the Yuan Dynasty. Although it was renamed Wanning, people still call it Haizi Bridge."
Wanning Bridge belongs to the category of "bridge sluice" and has dual functions: it is both a bridge for transportation and a sluice for water control. According to the "Jin Shi" records, there was already a sluice here during the Jin Dynasty, which was used to irrigate nearby farmland. This may be the predecessor of Chengqing Sluice. According to the "Yuan Shi·Guo Shoujing Biography", during the season when grain was transported from Tongzhou to Dadu City in the early Yuan Dynasty, it was raining heavily and many of the donkeys and oxen carrying the grain died. Guo Shoujing, the chief of the waterworks, presided over the excavation of the Tonghui River. After that, grain boats could go directly from Tongzhou to Haizi and store the grain in the newly built "Wanyi Warehouse" on the west bank of Haizi. In order to regulate the water level, Guo Shoujing also built a wooden Haizi Sluice at the starting point of the Tonghui River on the east bank of Haizi. According to "Hequ Zhi", in the first year of Zhishun (1330), this wooden sluice was rebuilt into a stone sluice connected with the stone-built Wanning Bridge.
In 2000, when the soil that had been buried under Wanning Bridge for many years was cleared, the stone sluice on the west side of the bridge was exposed. There were still stone grooves on both sides of the sluice for inserting the sluice gates, as well as stone winch frames for raising and lowering the gates. In ancient times, there were no powerful mechanical winches, and whole gates could not be used. Only multiple sluice gates could be stacked and inserted into the stone grooves. After the thick wooden sluice gates were soaked in water, they became even heavier, so manpower was needed to raise or lower them. When the sluice officer in ancient times ordered the sluice keeper to lower the sluice and store water, he would not say "maintain a water depth of several meters", but rather "lower the water by several gates".
The "Historical Records of Xiàxià" states: "Hǎizǐ Dōngchéngqīngzhá sān". The one located under Wanning Bridge is called the Upper Chéngqīng Lock. During the Yuan Dynasty, the arch of Wanning Bridge was higher than it is now. Grain ships from the south of the Yangtze River could sail directly to the waters of Jīshuǐtán after lowering their sails and passing through the arch of Wanning Bridge to anchor and unload their cargo. There were no obstacles between West Lake and Jīshuǐtán. At that time, Kublai Khan named the newly built canal "Tōnghuì River" when he passed through Wanning Bridge in his imperial carriage.
During the reign of Emperor Huìzōng of the Yuan Dynasty, the Grand Secretary of the Jíxián Academy, Xǔ Yǒurèn, wrote a poem: "The smoke is heavy on the willow tips, dripping with spring beauty, beside Tiānqiáo, living on Lánqiáo, blowing warm fragrant clouds, where is the sound of a flute..." Still unsatisfied, he wrote another poem called "Butterfly Loves Flowers": "After the new rain on the Nine Streets and Thousand Gates, the fine dye and thick fragrance fill the eyes like embroidered spring. It is just believed that the magical hands of the Eastern Lord have turned the official bridge willow green overnight..." The "Tiānqiáo" and "official bridge" mentioned in the poems both refer to Wanning Bridge.
Wanning Bridge is a single-arched Han white jade stone bridge, over 10 meters long and nearly 10 meters wide, with a stone-paved bridge deck that is slightly arched in the middle. The bridge has Han white jade stone guardrails on both sides, carved with lotus flower and treasure vase patterns. In the 1950s, the bridge deck was paved with asphalt, and houses were built on the filled river channel. The lower half of the bridge body is buried under the roadbed, and only the railings on both sides of the bridge remain. In 1984, it was declared a protected area and a construction control zone, mainly to protect its side walls and railing pillars. With the strong appeal of Beijing history experts such as Hóu Rénzhī, in 2000, the city of Beijing renovated Wanning Bridge, removed the billboards on both sides of the bridge and the houses on the river channel, and changed the hidden ditch to an open channel, restoring the water surface on both sides. While cleaning up the river silt for many years, several Zhènshuǐ Shíshòu (stone beasts that guard against water) were unexpectedly discovered. After examination, they were found to be relics from the Yuan and Ming Dynasties.
Wanning Bridge and the Zhènshuǐ Shíshòu, called Gōngfù Shíshòu, are one of the nine sons of the dragon. They are often placed in the middle of the bridge arch or palace drainage outlets because they like water. The unearthed Gōngfù Shíshòu are not only rare artistic treasures, but also rulers for measuring the depth of the river water. On the west bank of the bridge, a pair of claws holding water flowers, with their heads tilted down playfully, actually have a dragon ball and another Gōngfù Shíshòu looking up under the water.
As long as the river is full, this dragon ball and centipede snake will be submerged in the water, so few people have seen the scene of "two dragons playing with a pearl". A group of town water beasts on the north and south banks on the east side of the bridge are also very precious, especially the one on the north bank, which is particularly valuable. It is a centipede snake carved in the Yuan Dynasty, with an ancient and vigorous shape, about 1.8 meters long and 0.6 meters wide. The whole body is ink-colored, with whiskers under the mouth, scales on the limbs and tail, but no horns on the head. Unfortunately, the facial features cannot be seen due to severe weathering. Except for this stone beast from the Yuan Dynasty, the rest were added during the Ming Dynasty when Wan Ning Bridge was repaired.
Nowadays, the ancient Wan Ning Bridge has regained its youth. To the west of the bridge is the only imperial fire temple in Beijing. After several years of renovation, it was officially opened to the public in 2010. To the east of the bridge is the restored Jade River North section, where the gurgling blue waves flow downstream, reproducing the historical landscape of "water through streets and alleys" that disappeared for more than 700 years.
