List two great projects of the Sui Dynasty and talk about their locations

The Grand Canal of the Sui Dynasty

The Grand Canal of the Sui Dynasty was opened based on the existing natural river channels and ancient canals. It is divided into four sections: Yongji Canal, Tongji Canal, Hangou and Jiangnan River. With a total length of more than 2,000 kilometers, it is the longest canal in the ancient world. It starts from Hangzhou in the south, reaches Luoyang in the center, and reaches Beijing in the north. It spans eight provinces and municipalities including Beijing, Tianjin, Hebei, Shandong, Henan, Anhui, Jiangsu, and Zhejiang. It connects the five major rivers of Haihe, Yellow River, Huaihe, Yangtze River, and Qiantang River, and has become my country's The main artery of north-south transportation.

Daxing City (its ruins are located in a large area of ????Xi'an City, Shaanxi Province)

The original Han Chang'an City has been in ruins for a long time due to wars. Moreover, the palace was small and could not meet the needs of the newly unified national capital. In addition, urban sewage has accumulated over hundreds of years, making it difficult to discharge, and the supply of drinking water has also become a problem. Therefore, Emperor Wen of the Sui Dynasty abandoned the Han Chang'an City north of Longshouyuan and chose a new site to build the new Chang'an City in the southeast of Han Chang'an City south of Longshouyuan. In January 582, Emperor Wen of the Sui Dynasty ordered Yu Wenkai to be responsible for the design and construction of the new city. Because Emperor Wen of the Sui Dynasty had been granted the title of Duke of Daxing, it was named Daxing City and was completed in March of the following year.

Chang'an City covers an area of ??84.5 square kilometers. It is the largest capital city in the world and in ancient China. It is truly the first city in the world and laid a solid foundation for the prosperity of Chang'an City in the Tang Dynasty.

Daxing City refers to Luoyang City in the Northern Wei Dynasty and Nancheng, Yedu in the Northern Qi Dynasty. The city has a uniform layout and a rectangular shape. The whole city is composed of three parts: the palace city, the imperial city, and the inner city. It adopts an east-west symmetrical layout. The area of ??Lifang accounts for approximately 88.8% of the total area of ??the city. The substantial expansion of residential areas is a major feature of the overall architectural design of Daxing City. The city site is located on the Longshou Plain, bordering the Wei River to the north, Ba River and Chan River to the south. The terrain is high in the south and low in the north, with undulating hills in the south of the city. The "six slopes" south of Longshouyuan are regarded as the six lines of Qian, which are called Chujiu, Jiu2, Jiu3, Jiu4, Jiu5 and Shangjiu. According to the Book of Changes, the high slope on the ninth day of the lunar month represents "Don't use the hidden dragon". Jiuer Gaopo means "seeing a dragon in the field is a good way to see an adult". "Sir" represents a person with both virtue and status, so the palace city was built as the residence of the emperor. Jiusan Gaopo represents "A gentleman works hard all day long, is vigilant at night, and is strict without blame." He is always vigilant and not arrogant when he is in a high position, and he is not worried when he is in a low position. Therefore, the imperial city was built to keep the civil and military officials strong and loyal to the emperor. The concept of politics. The Nine-Five High Slope represents the "Nine-Five Supreme", which belongs to the position of "Flying Dragon" and is not intended to be occupied by ordinary people. [77]

So on the central axis of this high hill, the Daxingshan Temple (Buddhism) in the east and the Xuandu Temple (Taoism) in the west were symmetrically built in the east-west direction, hoping to use the gods to suppress it. The imperial spirit of Jiuwu Gaopo. Since Ziwei Palace, which represents the imperial palace, is located in the center of the north sky, the imperial palace can only be placed in the lower north. However, the Wei River leans on the north side, which is more suitable for defense [106]. The "six slopes" became the skeleton of Daxing City, with the royal palace, court and temples in sharp contrast to the general residential areas. In the lowlands between the hills and plains, canals were dug to divert water, lakes were dug, and the water channels of the city were enlarged. This makes full use of the advantages of the terrain, increases the three-dimensional space, and makes it appear more majestic.

There are also the Eastern Capital Luoyang built under the orders of Emperor Yang of the Sui Dynasty, and the Zhaozhou Bridge designed and built by Li Chun. Both of these are famous projects of the Sui Dynasty~~~~