The lifeline of Beijing's central axis

The emperors in ancient China all claimed to be the sons of heaven. They built a nine-story heaven, "facing south, the temple is connected with the sky", trying to construct the illusion that the sovereign power is "ordered by the sky" However, from the early Yuan Dynasty to the late Qing Dynasty, the place where 33 emperors worked and lived was not the direction of "due south and due north"-the central axis played a very important role in the architectural pattern of Beijing for more than 700 years, but today's experts and scholars found that it did not coincide with the meridian. ...

Aerial survey experts saw the panorama of Beijing and found something was wrong.

Kui Zhongyu, a researcher at China Academy of Surveying and Mapping, successfully took a panoramic image of Beijing with a special camera. This expert in aerial photography and remote sensing participated in several famous military reconnaissance in the early 1960s, with rich experience.

Facing the large-scale Beijing satellite image map and Beijing aerial image map, the old man felt that something was wrong, and his eyes were fixed on the central axis, which was the "backbone" that could affect the whole urban pattern, "whether it was Paris, London, Tokyo or Beijing".

On that day, Kui Zhongyu's line of sight was "northward" along the central axis of Beijing on the image map, and his head unconsciously deviated to the left, which surprised him-the central axis should be the direction of "due south and due north". "Is there a problem with air shooting?"

The central axis on the map is "eccentric" and "the bell tower deviates about 300 meters".

"Take a geographical coordinate and print it out. It (the central axis) deviates from the meridian by more than ten minutes, but less than two and a half degrees." Kun Zhongyu told reporters that after measuring the panorama, he came to this conclusion.

"Deviation of more than 2 degrees" once made Zhong-yu Kun question the accuracy of the panorama, but after comparing the topographic map of Beijing with the urban tourist map, this doubt was alleviated. Because, "not only image maps, but also topographic maps and even tourist maps, the central axis deviates from the meridian (meridian) without exception."

According to Kui Zhongyu, on the accurate topographic map, the central axis shows this kind of "deviation": it starts from the southern starting point (Yongdingmen) and starts to deviate from the meridian counterclockwise when extending northward, while the terminal position (Bell Tower) is about 300 meters away from the meridian after conversion!

Did surveying and mapping experts and cartographers collectively make mistakes?

The central axis of Beijing formed in the feudal imperial era coincides with the meridian, showing the direction of "due south and due north", which is the "natural truth" in most people's common sense. So, why is the central axis "crooked" in front of the world today? Is it that surveying and mapping experts and map makers have made mistakes?

Researcher Kun Zhongyu found those "map makers". Experts involved in surveying and mapping explained to him that they drew the map in strict accordance with field measurements, and after drawing, they also found that the central axis was crooked. They are also very confused. During this period, someone proposed to "straighten" the central axis on the map. ...

In the search, Zhong Yu further learned that in the early days of the founding of New China, surveying and mapping experts in Beijing had discovered this "deviation" in order to plan municipal construction. It is said that they have reflected this problem to the relevant departments, but historical facts cannot be changed. Because the deviation is relatively small, the public simply cannot feel it.

Experiments show that the axis in reality does deviate from the meridian.

In order to find out the direction of Beijing's central axis in reality, researcher Kui Zhongyu did an experiment at the end of last year, which was called "immediate effect". Under the newly-built Yongdingmen Gate, researchers made a sundial, erected a 2-meter-high pole, and stuck a 6-meter-long black tape on the Yonglu Road north of Yongdingmen Gate. The direction of the tape measure is the direction of the central axis, and the shadow of the pole represents the meridian.

After consulting the astronomical calendar in 2004 and counting the parallax correction value and longitude correction value, the experimental report was released: the black tape and the shadow formed an angle, and the measured angle was roughly -2 degrees for more than ten minutes!

"The central axis is indeed deviated." Kui Zhongyu said: "The central axis of Beijing is not the direction of due south and due north."

The reason for the deviation of the central axis dates back to more than 700 years ago.

Researcher Zhong-yu Kui had an in-depth discussion with many historians. First of all, it is clear that the existing central axis of Beijing is the central axis of the Yuan Dynasty. "When Genghis Khan conquered Beijing Zhongdu (now Beijing), it was completely destroyed. Later, the Yuan Dynasty established the Yuan Zhongdu on the basis of Beijing Zhongdu; In order to prevent the Mongols, the Ming Dynasty built the Deshengmen Line on the basis of the capital of the Yuan Dynasty, and the east and west walls followed the earthen city of the Yuan Dynasty, enclosing the walls with the direction of the central axis unchanged. Ming city was used in the Qing dynasty, and the central axis has not changed. It has been more than 730 years since today. "

There are different versions of the mystery of the central axis, one of which is that "the Han people did it on purpose." Why the central axis is skewed, the focus of attention naturally focuses on the project host. So who presided over the construction of the central axis of the Yuan Dynasty? Kui Zhongyu said that Kublai Khan's prime minister Liu was in charge of supervision. It is generally believed that the central axis of the Yuan Dynasty was built by Liu, a native of Xingtai, Hebei, and his student Guo Shoujing.

In view of the historical fact that the Yuan Dynasty carried out the policy of national oppression, some historians put forward that the central axis was deliberately deviated by Liu Hanchen, Zhong Bing and Guo Shoujing, that is, it did not comply with the emperor's will, so that the central axis affected the urban layout on the meridian of due south and due north in an attempt to resist the rule of the Yuan Dynasty.

In this regard, some scholars questioned, because the above statement could not produce convincing evidence. So there is a second view: it may be that the builder adopted the magnetic needle positioning method, which caused technical mistakes. However, Kui Zhongyu thinks this reasoning is unconvincing. After all, Liu and Guo Shoujing were outstanding scientists at that time, and they could use high-precision astronomical measurement methods. However, "it is unlikely to use a magnetic needle that proved to have a great error at that time." In addition, there is a saying that the central axis may be skewed due to the destruction of natural factors. Kui Zhongyu was surprised to find that the central axis pointed to the ruins of Shangdu in the Yuan Dynasty.

Kui Zhongyu mainly introduced Kublai Khan, the grandson of Temujin, the first emperor of the Yuan Dynasty. "This central axis was built during Kublai Khan's reign. Is its formation also related to the local yuan that Kublai Khan rose? "

With questions, Zhong-yu Kui and others continued to measure maps and conduct field trips. Finally, they found that the central axis of Beijing continued to extend northward, and the extension line just passed through Gukaiping, which is more than 270 kilometers away from Beijing, that is, Zhaonaiman Sumer in Xilin Gol League, Inner Mongolia Autonomous Region.

According to local Mongolian historians, Zhaonai Mansumi is the site of Shangdu ruins in Yuan Dynasty. That's where Kublai Khan moved his capital to Yuandadu (now Beijing). In fact, Kublai Khan practiced a "two-capital patrol system" in Yuan Shizu: he worked in the Yuan Dynasty in winter, which was the so-called "winter capital"; In summer, I work in Yuanshangdu, which is "Summer Capital".

Therefore, researcher Kui Zhongyu believes that the fact that the central axis deviates is intentional by Kublai Khan, the founding emperor of the Yuan Dynasty. Because the archives of the "Mongolian Empire" in Yuan Dynasty are not complete, scientists and historians are still struggling to find the answer in specific textual research and reasoning.

Kui Zhongyu said that from Yongdingmen in the south to the bell tower in the north, Beijing's current central axis is 7.7 kilometers (8 kilometers reported by the media), which should be regarded as the "southernmost tip of the two capital lines" about 270 kilometers from the site of Yuandadu to Beijing.

According to experts' statistics, 33 feudal emperors in history took Beijing as their capital. From this point of view, these 33 so-called "the only thrill", except perhaps Kublai Khan and others, may not even know that their dragon chairs are "crooked". Mario botta, a contemporary famous modernist rational architect, came to China from Switzerland and wandered among the magnificent buildings of the Forbidden City. He said to the architect in China, "You don't need to move western things, just study the Forbidden City thoroughly. You see, there are only two or three colors in the Forbidden City, and two or three building materials are used to create such a shocking architectural environment with such simple things! "

Liang Sicheng 195 1 April, "Beijing-An Unparalleled Masterpiece of Urban Planning" described this axis:

We can start from Yongdingmen at the southernmost tip of the outer city. From the main entrance at the southern end to the north, there are two roughly symmetrical buildings around the central axis: the Temple of Heaven and the Xiannongtan. After crossing a long street opposite the gate tower, we arrived at the crossroads of zhushikou, and then faced the first focus of the inner city-the majestic Zhengyangmen Building. In front of the door 100 meters, a big archway and a big stone bridge blocked it, which is very avant-garde for this first point. But this is just the beginning. Since then, from Zhengyangmen to Zhonghua Gate, from Zhonghua Gate to Tiananmen Square, it has risen again and again. The length of the Imperial Road in the middle of the Thousand Steps Gallery (demolished in the early years of the Republic of China) and the width in front of Tiananmen Square are the boldest space treatments, which set off the arrangement of architectural priorities. Starting from Tiananmen Square, there are a series of palace gates and courtyards with different weights. The glazed tile roof is glittering and ups and downs, reaching the top of the Hall of Supreme Harmony, reaching its peak in the first half of the central line, and then gradually retreating to the north, ending at Shenwumen. Further north, Jingshan, which stands with "Qifeng protruding", sets off the back of Miyagi. The pavilion on the top of Jingshan Mountain is in the center of north and south. Starting from this, going north is the echo of the key points of long distance. From Di 'anmen to Drum Tower and Bell Tower, high-rise buildings continue on the central axis. But in the bell tower, the central axis ended in a planned way, and just right. The center line will no longer reach the wall base in the north, but will smoothly distribute the center of gravity to the two towers in the north-Andingmen and Deshengmen, which are separated from each other. There is no second construction site plan with such charm in the world!

1264, Kublai Khan gave up Jindu and chose a place in the northeast to establish the capital of the Yuan Dynasty, which was the predecessor of Beijing in the Ming and Qing Dynasties. The delineation of the central axis plays a decisive role in the planning and construction of the Yuan Dynasty. Planners use the vast water surface and beautiful natural lake scenery of Shichahai and Beihai in Beijing to build the city. In order to prevent the central axis from getting lost in the lake, the designers of Yuandadu drew a straight line tangent to the lake from north to south on the east bank of the arc lake. The tangent point is today's back door bridge, and the tangent point is today's central axis.

After the destruction of the Yuan Dynasty in the Ming Dynasty, the Yuan Dynasty was rebuilt, and the central axis still extended southward. By the time the outer city of Beijing was completed in the 0/6th century A.D./KLOC, this magnificent architectural corridor we saw today gathered large buildings such as Zhengyangmen, Tiananmen Square, Forbidden City, Jingshan, Drum Tower and Bell Tower. It is dominated by gold and red, and the quadrangle with green bricks, gray tiles and green branches is quiet.

The construction of Beijing follows the principle put forward by China's ancient urban construction classic "Zhou Li Kao Gong Ji": "Artisans rule the country, nine miles away, there are three doors next to it; The ninth day passes through nine latitudes, nine tracks, left hand and right hand, facing the market outlook. " Through the tangent line between the central axis and Shichahai, natural lakes are boldly introduced into the urban area, and the layout of the whole city is determined, which embodies the Taoist thought of "man, earth, heaven, heaven, Taoism and nature" and integrates Confucianism and Taoism into the construction of China capital for the first time. In 2005, the State Council approved the master plan of Beijing, and determined the pattern of "two axes, two belts and multiple centers". One of these two axes is the north-south axis, which is the historical axis; The east-west axis is newly formed, that is, after 1949, it passes through Tiananmen Square and Chang 'an Avenue from west to east. The two central axes form a cross frame, the east-west central axis represents a context of contemporary Beijing development, and the north-south central axis confirms a context of Beijing history.

The early concept of the central axis was trans-axial symmetry. Influenced by Huang Lao's inaction, Chang 'an in the Western Han Dynasty formed the concept of no axis. During the Wei, Jin, Tang and Luoyang periods, influenced by the imperial power, a "palace-dominated type" was formed. After passing through the capital of Song and Jin Dynasties, it arrived at the capital of Yuan Dynasty, and formally formed the type of "former dynasty and market outlook". This central axis fully embodies the political value, ethical value and aesthetic value, and finally formed an overall connection in the Ming and Qing Dynasties. In all previous dynasties, the central axis of Chang 'an in Tang Dynasty was the longest, 8.65 kilometers. Not counting the palace, it's actually 7. 16 kilometers. Although Luoyang runs through the north and south, it is 6.8 kilometers long, but it is on one side, so the longest central axis running through the whole is the Beijing central axis, with a total length of 7.86 kilometers.

The history of Beijing's central axis can be traced back to the Yuan Dynasty. Kublai Khan of Yuan Shizu gave up Jindu and chose the northeast place to establish the capital of Yuan Dynasty, which was the predecessor of Beijing in Ming and Qing Dynasties. At this time, the central axis is 3.7 kilometers long. In the early years of Ming Dynasty, General Xu Da demolished the North Wall of Yuan Dynasty and moved it to the south. The metropolitan wall is still used in the east, west and south, with a central axis of 4.78 kilometers. During the Yongle period of the Ming Dynasty, the Forbidden City was built along the central axis of the Yuan Dynasty, and the imperial city began to be built, pushing the southern wall of the Yuan Dynasty to the south for 2 miles, thus forming the inner city of Ming Beijing. During the Jiajing period of the Ming Dynasty, in order to strengthen the security of the capital, the outer city of Beijing was built. After the Qing Dynasty made Beijing its capital, there was no major change, but the pattern of the Ming Dynasty was followed, with a central axis of 7.86 kilometers. The spatial pattern of Beijing's central axis is: the dragon head: Yandun and Qianlong Monument. Yandun, commonly known as Yandun, is a pier about 8 meters high, on which stands a royal stone tablet made by Emperor Qianlong of the Qing Dynasty. The tablet is engraved with the inscription written by Emperor Qianlong in Manchu and Chinese, which describes the general situation of Yanjing capital and is an important historical and cultural landscape in Beijing. Tianjie: Shiqiao Overpass outside Yongdingmen, with a length of1650m. Yongdingmen has no gatehouse, and it goes straight down to the watchtower. There is an urn between the watchtower and the watchtower. There is a big gate in the outer city, which is Guang 'anmen. At that time, people who went to Beijing rarely entered Yongdingmen, but generally took Guang 'anmen, because outside Guang 'anmen was the main official road leading to the Central Plains and the South. After coming in from Yongdingmen, it is Tianjie, with the Temple of Heaven and the Xiannongtan on one left and one right. In the Ming dynasty, the Temple of Heaven was called the altar of heaven and earth, and heaven and earth were sacrificed together. Xiannong altar is called Shanchuan altar, offering sacrifices to famous mountains and rivers in the world. Cheng Nan Commercial Street: Tianqiao-Pan Qi Street, length1780m. Outside the north wall of the Temple of Heaven and the Xiannongtan, there is a ditch from west to east called Longxugou, which means that the heaven is a dragon, and the ditch is like two whiskers of Longkou. There is a bridge across Tianjie in Longxugou, which is called overpass. Further north, it is Zhengyangmen. Of the nine gates in the inner city of Beijing, only Zhengyangmen has two gates, which enter from both sides. There are two temples in Zhengyangmen Wengcheng, Kannonji in the east and Guandi Temple in the west. After entering the city, it is Chessboard Street.

Nanhuangcheng: Daqingmen-Duanmen, 850 meters long. There is a leader in front of every important building on the central axis. The gate of the imperial city is generally considered as Tiananmen Square, but it is actually the gate of the Qing Dynasty, the south gate and the predecessor of the imperial city. After the Qing gate came in, it was a T-shaped square surrounded by the imperial city wall, with Chang 'an left gate and Chang 'an right gate at both ends. There are two rows of long houses between Tiananmen Square and Daqingmen, which were later called Qian Qian Lang. Imperial Palace Garden: Duanmen-Jingshan, length 1990 meters. The end door is actually the main entrance of the imperial city. After entering the end gate, there are official offices on both sides, ready for the emperor's summons. Corresponding to the end gate is the north gate outside the Shenwumen. North Imperial City: Jingshan-Di 'anmen, 570 meters long. Beyond Jingshan, there are two buildings called Yanchi Building, followed by two yellow tiles and red walls, and two buildings at the northern end, also called Yanchi Building. This wall is in the imperial city. In the past, people called it "Lihuangcheng", and the door on the wall was called Huangwamen, so the wall can also be called Huangwamen. Beicheng Commercial Street: Di 'anmen-Bell Tower, length1020m. The important building north of Di 'anmen is Wanning Bridge, commonly known as Houmen Bridge by Beijingers. It is the gateway of Tonghui River into Jishuitan (Shichahai) in Yuan Dynasty, and it can be said to be a symbol of the northern end of the Grand Canal in China.