The Great Wall, so far as its gigantic scale and difficulties in its construction are concerned, is beyond doubt a civil engineering project of defense, the greatest of its kind in ancient China. It can certainly be regarded as one of the great wonders ever wrought in the history of mankind. The Great Wall, a glory of the Chinese nation, is the symbol of the ancient culture and the long-standing history of China. Baptized by nature for thousands of years, the Great Wall has witnessed the rises and falls of innumerable dynasties and changes on the earth, yet is still ranging proudly in the east of the world. Today, the Great Wall, however, as a work of military defense against harassment and invasion from without, has become things of the past, yet instead it is playing a role in bridging up the friendship between the Chinese people and the people of the rest of the world.

The Great Wall, snaking along the north of China with its starting point from the Old Dragon Head of the Shanhai Pass at the seaside in the east, stretches westwards over a distance of 10,000 li (1 kilometer= 2 lis). It crosses three provinces, two municipalities and two autonomous regions. Its actual length totals about 6,300 kilometers, an equivalent of about 3,915 miles.

During the time of Warring States Period (475-221 B.C.), all the principal states had the walls built in the bordering areas of the territories in order to defend themselves and against the infringement from the neighboring states. And to ward off the harassment by the Huns (an ancient nomadic tribe in China) from the north, the three states of Qin, Zhao and Yan had high walls and fortresses built along their northern frontiers. This is the origin of the present-day Great Wall. In 221 B.C., the first emperor of the Qin Dynasty unified the whole China by defeating the six other ducal states. To prevent from disturbing and attacking by the Huns, the emperor gave order to link up all the walls built by the former ducal states along the northern frontiers, thereby forming the world famous "10,000-li Great Wall". The succeeding dynasties after the Qin kept on the work of maintenance and repairs or having parts reconstructed again and again. The project carried out in the Han and Ming dynasties were the greatest on scale in the old days of China.

The Great Wall is the traditional defensive project through ages. It mainly consists of passes, walls, watchtowers and beacon towers. As the wall inched across the Chinese wilderness, its builders were forced to rely upon local materials. Some wall was built with tamped-earth, some with stone, some with tamped mixture of reed, red willow, and sands, and some with bricks outside and stuffed earth and sands inside. Most of the walls we see today are Ming walls, which were mainly made of stone and bricks. Watchtowers are the key parts of the military construction. Very close to each other, brick towers could be two storyed or 3 storyed. On the top of the tower, there is a small room, which is surrounded by battlements. The watchtower can be used to station soldiers or store food and weapons. Thousands of passes stretch along the Great Wall. Some are between the mountains, some betwent the mountains and rivers, and some between the mountains and sea. Passes are the gateways of transportation and become the strongholds during the war. Beacon towers are the communicational facilities. Emergent military messages could be delivered by beacon tower in a short time.

The Great Wall snakes from east to west, and looks like a dragon on the Oriental. Presently there are five sections of the Great Wall opened to public in Beijing, including Badaling section, Juyong Pass section, Mutianyu section, Jinshanling section and Simatai section.

Badaling Section
Sixty kilometers northwest of Beijing, Badaling section is the outstanding part of the Great Wall. Lying in the Yanqing District, it provides vital protection for the Juyong Pass, one of the key passes of the Great Wall. Commanding the strategic importance, Badaling section is known as "giving access to every direction", hence the name Badaling.

Badaling is one of the earliest places to build walls. To resist the marauding of the nomadic tribes, defensive construction of the wall emerged along the Yanshan Range during Spring and Autumn Period and Warring States Period. The Badaling section was fortified continuously by the following dynasties. The wall we see today was built in Ming Dynasty (1368-1644 A.D.) along the ridges of mountains. The construction lasted about a hundred years long from 1505, the 18th year of Emperor Hongzhi, to the reign of Emperor Wanli.

The huge wall was built to be strong and firmly, encased in a facing of kiln-fired bricks, bases on the foundation of granite slabs, and covered with bricks on the top. The slots were all stuffed with pulverized lime, which enabled the wall to be smooth. The wall is 8.5 meters high, 6.5 meters wide at the bottom and 5.7 meters wide on the top, which makes it possible for 5 horses or 10 people march abreast on the top. Watchtowers spaced 0.5 or 1 kilometer apart. Those watchtowers were full of vigor and grandeur, and orderly spotted the wall. The battlements and embrasures of the watchtower serve well in wartime. Rising abruptly to the peaks of each sideof the Badaling, the wall winds its way along the ridge of the Jundu Mountain. Seemingly endless, it wanders far away into the remoteness. The wall of Badaling has a total length of 3, 741 meters.

Badaling was the earliest section to be open to the tourists among all the parts of the whole Great Wall. 130 million tourists from China and abroad have visited Badaling; 370 foreign leaders and very important persons have come to climb Badaling successively.

Mutianyu Section
Lies in Huairou District, Mutianyu section is 75 kilometers northeast of Beijing. It links with Juyong Pass in the west and Gubeikou Pass in the east. Commanding the strategic importance, Mutianyu section is called as the Majestic Pass on Precipitous Mountains.

Due to its relatively gentle terrain, watchtowers of Mutianyu section were built in large numbers to strengthen its defensive functions. The closest watchtowers spaced less than 50 meters apart. Both arms of the Mutianyu section stretch upwards along the ridges of continuous mountains. Mainly built on precipitous mountains and 5-7 meters high, the Mutianyu section we see today is expanded on the foundation of the Ming Dynasty wall. It is characterized with a thick cluster of watchtowers atop, strategic passed, majestic vigor and unique structure. The gate tower is the most unique building of this section.

Simatai Section
Started from Wangjing Tower in the east and connected with Jinshanling section in the west, Simatai Section lies in the Miyun County, 120 kilometers away from Beijing. This section is a largely unrestored and more authentic section of the Great Wall, not crowded with hordes of other tourists.

Simatai section was started to be built during the early years of Ming Emperor Hongwu. A renovation was applied from 1569 to 1573. Located in mountainous area, it was mainly built along the ridge of the mountains. Featuring in uniqueness, ruggedness and trimness, it perfectly coordinates with the undulating terrain, which makes it more majestic and magnificent. At the foot of the central part of the Simatai section, there is the Simatai reservoir, which is 600-700 meters long with the storage capacity of 50,000 cubic meters.

Simatai section is the most wonderful part of the Great Wall. The walls and watchtower take good advantage of the fluctuating terrain and constitute the most essential part of the wall. It boasts precipitous cliffs, magnificent towers, suspension walls and rugged stairways. Looking from afar, the Great Wall is like a flying dragon in the cloud. Standing nearby, the wall meanders its way along the ridges of mountains. No wonder the Simatai section is regarded as the most amazing part of the Great Wall.

Jinshanling Great Wall
Jinshanling is situated 155 kilometers north of Beijing. Jinshanling is the name given to an eleven kilometre section of the wall situated on the Jinshan Mountains. The earliest bit of this structure was built in the 6th Century AD, but most of what you see now dates from the Ming Dynasty. This section of the wall has 67 watchtowers, each built in a different style of architecture. The walkway along the top is paved with square bricks providing a level surface wide enough to construct or erect batteries. Poems and tablet writings can be found on the Jinshanling Great Wall left from the time General Qi Jiguang directed building of this section of the Great Wall. Barrier walls were built leading to the enemy towers to protect the towers. Some of the towers were storerooms for food, hay and weapons.

Gubeikou Great Wall
Gubeikou is located 145 kilometres north of Beijing. It has the Panlong (Coiling Dragon) and Wohu (Crouching Tiger) mountains in the background and is linked to the Qingfeng (Green Wind) and Dicui ( Piled Verdure) peaks. The Chaohe River runs across the foot of the wall from north to south. In 1378, General Xu Da ordered this section of the Great Wall rebuilt. Gubeikou has seen probably more battles than any other part of the Great wall, including some of the most famous in Chinese history. On the southern slope of Gubeikou stands a temple dedicated to Yang Ye, a famous Great Wall garrison general of the Song Dynasty. There are quite a few temples in China dedicted to this general, but this one is perhaps the oldest.