China's first dynasty was Xia, XXI years BC; which corresponds to an era of slavery. To protect themselves against slaves' rebellion but also against foreign aggressors the owners built walls around their properties. And yet those first fortifications were not yet made of stone nor bricks; they used to be terre-pleins or earth walls tapped by watch towers. This is how the first cities were born in China.

   Around 500 BC: The period of Spring and Autumn (770-476 BC) but mostly during the age of Warring States Period (475-221 BC) the Wei, Zhao, Qin and Yan Principalities from the North of China endowed themselves of defensive walls, later built along the rivers, in order to protect themselves from one another, or against northern barbarians. In fact, these wanderers were only the tribes that the Principalities had either progressively pushed away to the North, or absorbed, by depriving them of their estates.

   Between 221 and 206 BC: Once the Great Wall Of China was unified, and from the beginning of his reign, the First Emperor Qin Shi Huangdi (whose tomb contained 8000 life-size terracotta warriors) decided to unify the already existing parts in order to pursue his policy of expansionism and to erect the Great Wall Of China. The first accomplishements of the Great Wall Of China became visible. They all started from the region of Lanzhou, in the Gansu, to end in the Liaodong peninsula, close to Corea, tracing the outline of the bend of the Huang He (Yellow river). Its layout followed sections of older defensive walls, which were thus joined together, extended and braced.

   Between 206 BC and 220 AD: The Han Dynasty continues the construction of the Great Wall up to the west of what is today known as the Gansu Province, 300km from Yumen. The wall reaches 10 000km!

   Between 386 and 550: The Northern Wei Dynasty links the 2 main axes of the Han in the North of Hohhot, and encircles the surroundings of the city of Datong, in the Shanxi region.

   Between 550 and 577: The Northern Qi Dynasty raises the northern wall of Datong and builds up a new section of 500km.

   Between 581 and 1066: To control the Tibetan and Tujue Turcs' invasion, the GWOC is braced during the Sui Dynasty (58-618) During this time, no new important section of the wall will be built.

   Between 1066 and 1125: The Liao Dynasty sets up a whole new Great Wall in the North of Mongolia, in the Manzhouli region.

   Between 1125 and 1234: The Jin Dynasty extends the wall along the eastern border of Mongolia by more than 2000km, between Qiqihar and Baotou.

   Between 1403 and 1435: After the loss of interest of the Tang, Song and Yuan Dynasties, the Ming undertake the fortification and/or the reconstruction of the existing defences which coincide with the main activity of the Mongols, who are threatening the North of the Empire. The Great Wall is then separated in nine different military areas called Zhen.

   Between 1438 and 1449: The growing threat of the Mongols, due to the capture of the Emperor in 1449 by the Oirats (a Mongol group of people in China), the Ming have doubled their fortifications inside the empire.

   Between 1465 and 1487: A new section of the Great Wall Of China is built inside the sweep of the Yellow River.

   1598: Conclusion of the Great Wall in the Northern region of Lanzhou.

   After 1644: Under the Qing Dynasty (1644-1911), the establishment of the Manchu protectorate upon Mongolia, withdraws the military meaning of the Great Wall, but it still materializes the border between China and the fields and allows, to a certain extent, the control of the comings and goings.

   1961: The Council of China’s State Affairs publishes a decree stating that the Shanhaiguan Gates Juyongguan and Jiayuguan are scheduled as ancient monuments and sites of great value, protected by the State.

   1987: Registration of the Great Wall on the UNESCO XXXX (United Nations Educational, Scientific and Cultural Organisation).

   1991: Russia being dissolved, satellites were allowed to fly over Mongolia to view the Liao Dynasty's Wall.

   2001: A section of 500km, bating back from the Han Dynasty, is discovered west of the Yumen.