HISTORY;
The Construction of the Great Wall first began during the warring period of 476 - 221 B.C. In the beginning walls were built at some strategic points by different kingdoms to protect their own territories. After the first Emperor Qin Shihuang of the Qin Dynasty unified China in 221 B.C., he decided to have the individual walls joined together creating one Great Wall, he also built new walls on top of the base of the original walls... it took more than 1 million people and more than 10 years to finish his work... subsequent dynasties continued to strengthen and extend the wall, in particular the Ming Dynasty from the period between 1386 - 1644 A.D.

CONSTRUCTION CHARACTERISTICS;
Before the use of bricks, the Great Wall was mainly built from earth, stones and wood. Transporting the large quantity of materials required for construction was difficult, so builders always tried to use local resources. Over the mountain ranges, the stones of the mountain were exploited and used, while in the plains, earth was rammed into solid blocks to be used in construction.

Before and during the Qin Dynasty (221-206 BC) because earth buildings could withstand the strength of small arms such as swords and spears, combined with low technology of productivity, the Great Wall was primarily built by stamping earth between board frames. Consequently walls were built consisting of just earth or a mixture of earth and gravel. No fortresses were constructed along the wall, and no bricks were used in the gates at the wall's passes. Much of these sections have eroded away. During the time following the Han Dynasty (202-220 AD) earth and crude stones remained common building tools.

Bricks were heavily used in many areas of the Great Wall during the Ming Dynasty, as well as materials such as tiles, lime, and stone. Bricks were easier to work with than earth and stone as their small size and light weight made them convenient to carry and augmented construction speed. Additionally, they could bear more weight and retain their integrity than rammed earth. Stone, though more difficult to use, can better hold well under its own weight than brick. Consequently, stones cut in rectangular shapes were used for the foundation, inner and outer brims, and gateways of the wall.

The steps that form the Great Wall of China are very steep and tall in some areas of the wall. Tourists often become exhausted climbing the wall, and traverse no more than a mile because of this reason. Along the wall on either side, are “holes” where the builders of the Great Wall didn’t place any bricks. They are a little over a foot tall, and about 9 inches in width. These holes were used to shoot arrows out of when being attacked.

Generally speaking; the wall is narrow on the top and broad on the bottom forming an adder-shape structure. This made the wall stands firmly on the rise and fall ridges. The wall was built with 10-14 rectangular slab of stones surrounding its outside, filled with soils and stones in the middle, and paved with square bricks on the top between the bricks were stuck with lime stones. This makes the wall tidy, beautiful, and firm. There are gutters with gargoyles to drain rain-water off the parapet wall.

SPECIAL SECTIONS OF THE GREAT WALL;
The “North Pass” of Juyongguan Pass is known as the Badaling... this particular area of the Great Wall is where most tourists visit due to its proximity to Beijing City and the condition of it's restoration... the Badaling Great Wall climbs up and down, twists and turns along the high mountain ridges and occupies commanding and strategic positions... the Great Wall section at Badaling fully shows the quality of ancient Chinese labor.

The Badaling Great Wall was built in the 18th year of the Ming Hong Zhi reign (1505). The wall, built with high stone slabs on the outside, is 7.8 meters high on the average, some even reaches 8.4meters. The base of the wall was built with more than 2000 large rectangular slab of granite stones. It is about 6.5 meters wide on the average at its base and 5.7 meters wide on the average on the ramparts. The wall is wide enough for five horses to gallop abreast and ten people to advance shoulder to shoulder. The outside of the wall is called rampart wall. The rampart wall was built with bricks 1.7 meters high. Built for the purpose of defense, there are holes on the tip of the wall called watch-hole, and peepholes under the wall called embrasures. Inside of the wall, there are low walls with one meter high called parapets, which can be used as railings. There is a scroll door not far from the inside wall, with is a stone ladder for climbing up and down.

Representing the Ming Great Wall, Jinshanling is considered to have the most striking sights of the Great Wall. It runs 11 kilometers long, ranges from 5 to 8 meters in height, and 6 meters across the bottom, narrowing up to 5 meters across the top... Wangjinglou is one of Jinshanling's 67 watchtowers, rising 980 meters above sea level.

Shanhaiguan Great Wall is referred to as the "Museum of the Construction of the Great Wall", because of the Meng Jiang-Nu Temple which was built during the Song Dynasty. The Shanhaiguan Great Wall is known for many different things, both with the construction of the wall, and also its history.

The first pass of the Great Wall was located on the Shanhaiguan (known as the "Number One Pass Under Heaven"), the first mountain the Great Wall climbs, Jia Shan, is also located here, as is the Jiumenkou, which is the only portion of the wall that was built as a bridge.

CURRENT CONDITION;
While some portions near tourist centers have been preserved and even reconstructed, in many locations the Great Wall is in disrepair, serving as a playground for some villages and a source of stones to rebuild houses and roads. Sections of the Wall are also prone to graffiti and vandalism. Parts have been destroyed because the Wall is in the way of construction sites. Intact or repaired portions of the Wall near developed tourist areas are often plagued with hawkers of tourist kitsch.

The portions of the Badaling section of the Great Wall have been restored... the Badaling Great Wall is where most tourists visit due to its proximity to Beijing City and the condition of the restoration.

WATCHTOWERS;
The Great Wall was built with more than 10,000 watch towers which were used to store weapons, house troops, and send smoke signals... each tower has unique and restricted stairways and entries to confuse attackers. Barracks and administrative centers are located at larger intervals. Communication between the army units along the length of the Great Wall, including the ability to call reinforcements and warn garrisons of enemy movements, was of high importance. Signal towers were built upon hill tops or other high points along the wall for their visibility.