Great Wall of China

One of the country's most significant representations of culture and history is the Great Wall of China. The wall takes the shape of a gigantic dragon. It winds across northern China from east to west, passing through deserts, grasslands, mountains, valleys and plateaus. The wall is over 4,000 miles long, with an average height of 40 feet and a width of 16 feet.

The first part of the wall was built in 770 BC and the construction continued on for centuries, when each dynasty continued to add more. It was built in order to protect China from raids by the Mongols and Turkic tribes. The primary purpose of the wall was not to keep out the people who could scale the wall, but to insure that semi-nomadic people on the outside of the wall could not cross their horses or return easily with stolen property. During those times, the weaponry only consisted of swords, spears, lances and bows and arrows, nothing strong enough to defeat the structure of the wall.

The wall was one of the most strategic military structures. It is complemented by defensive fighting stations, to which wall defenders could retreat if overwhelmed. Each tower has unique and restricted stairways and entries to confuse attackers. Barracks and administrative centers are located at larger intervals. And, in addition to the usual military weapons of the period, specialized wall defense weapons were used. The watch towers, which were spread about a half mile apart were used to house troops, send smoke signals and store weapons.

The materials used were those available near the site of construction. Near Beijing, the wall is constructed from quarried limestone blocks. In other locations it may be quarried granite or fired brick. Where two such materials are used, two finished walls are erected with earth and rubble fill placed in between with a final paving to form a single unit. In some areas the blocks were cemented with a mixture of glutinous rice and eggwhite. In the extreme western desert locations, where good materials are scarce, the wall was constructed from dirt rammed between rough wood tied together with woven mats.

Even today, new parts of the wall are being discovered. In Oct. 2002, a 50 mile section of the wall was discovered in northwestern china, centuries after being submerged by the sands that move across the arid area each year.

The Wall is included in lists of the "Seven Medieval Wonders of the World" and it was made a UNESCO World Heritage Site in 1987.