The famous Great Wall of China has several entrances and can be visited from different places because of its several thousand kilometer lengths. Over the years there are several places on the wall which are ruined, and there are other places that are in excellent condition. The entrance fees are also different from the different entrances. In some of the cases, the admission fee is doubled as if you want to hike from Jinshanling to Simatai.
Many myths associated the construction of the wall to the Qin Shi Huang Di Era in the 2nd century B.C. But infarct the walls that we see in the current day are constructed much later than the Qin Shi Huang Di Era. This great wall can be described as a series of walls built by different emperors at different times.
First Great wall
It was Qin Shi Huang Di who after unifying China for the first time, ordered to build the First Great Wall in the year 2014 BC. This was to protect from the raids by the Xiongnu raiders from the north. It was the effort of 500,000 laborers to build the first wall and took about 32 years to built the wall.
The first wall was quite successful in defending its land from the external enemies but was unable to stop internal pressures that led to change in regime in 206 B.C. After this, the newly formed leader saw the immense usefulness of the wall in stopping the outside raiders, and he decided to stretch the watt a bit more. He ordered to stretch the wall to the Zhaoxiang, Gansu Province.
Second Great Wall
The Han Dynasty were fighting against the Raiders for 70 years, and in this period there were several places where the raiders damaged the wall. In the year 130 B.C. Emperor Wudi of the Han Dynasty ordered a commission to rebuild and fortify the original wall. The emperor was quite successful in adding more regions to this rule, and then in 127 B.C., he ordered the expansion of the wall that created the second wall outposts. The outposts were in Zhangye, Wuwei, Jiuquan, Dunhuang and Yumenguan in Gansu Province and Lopnor and other outposts in Xinjiang Province. The wall was then extended to the Hexi Corridor. This was the corridor through where the Silk Road traders would travel.
Then there was a time when the Han Dynasty fell apart, and three kingdoms of the Wei, Shu, and Wu were formed. It was the northern Wei kingdom that took the initiative to continue rebuilding the great wall to keep the Rouran and Qidan nomads out from their place. After that Wei kingdom, Sui kingdom got merged and was defeated by the Tang Dynasty in 618 AD.
After this, there was a gap when nothing was done to the great wall. Then the Liao and Song dynasties came into power. Khitans ruled the Liao Dynasty was controlling the north and Song Dynasty controlled the south. Jurchen was the tribe that troubled the Liao Dynasty from the northeastern region. This led them to build a wall along the Heilong and Songhua rivers. This was unsuccessful to stop the raids from the southern region.
Third Great Wall: Jurchens were finally able to establish the Jin Dynasty in the year 1115. They understood that the Mongols were behind them. That was when the Jin emperor ordered to construct a third wall in the Heilongjiang Province and Inner Mongolia Autonomous Region.
The Mongols were successful in defeating the Jin Dynasty in 1276 although the wall was standing there. Then they established the Yuan Dynasty. During the period of the Yuan Dynasty, the wall was in a very bad shape, and that was when Chinese Ming Dynasty took the control.
The Ming Dynasty understood the complications of foreign rules, and they decided that they would never let this thing happened again. Hongwu, the first ruler of the Ming Dynasty, started manning of the Great Wall. They built fortresses and garrison along the wall. The fort of Jiayuguan was built in the year 1372.
Fourth Wall: After gaining interest in rebuilding the great wall, significant and the best work was done in between the year 1569 and 1583. This gave the shape to the fourth great wall. This wall managed to keep the Mongols away several times.
Again in the year 1644, Jurchens regrouped, and Manchus were formed who retook the region of China. They formed the Qing Dynasty. This was the time when the wall started fading away as the stones of the walls were taken for construction purpose. That was the worst period for the wall until recently in the year 1984; President Deng Xiaoping ordered the restoration of this legendary wall. In the year 1987, UNESCO declared the wall to be a Cultural World Heritage Site.