The Great Wall - Beijing 2007

The Great Wall of China (Wànlǐ Chángchéng; literally "The long wall of 10,000 Li) is a series of stone and earthen fortifications in China, built, rebuilt, and maintained between the 5th century BC and the 16th century to protect the northern borders of the Chinese Empire during the rule of successive dynasties. Several walls, referred to as the Great Wall of China, were built since the 5th century BC, the most famous being the one built between 220 BC and 200 BC by the first Emperor of China, Qin Shi Huang. That wall was much farther north than the current wall, built during the Ming Dynasty, and little of it remains.

The Great Wall is the world's longest human-made structure, stretching over approximately 6,400 km (4,000 miles) from Shanhai Pass in the east to Lop Nur in the west, along an arc that roughly delineates the southern edge of Inner Mongolia. It is also the largest human-made structure ever built in terms of surface area and mass.

History
The Chinese were already familiar with the techniques of wall-building by the time of the Spring and Autumn Period, which began around the 8th century BC. During the Warring States Period from the 5th century BC to 221 BC, the states of Qi, Yan and Zhao all constructed extensive fortifications to defend their own borders. Built to withstand the attack of small arms such as swords and spears, these walls were made mostly by stamping earth and gravel between board frames.

Qin Shi Huang conquered all opposing states and unified China in 221 BC, establishing the Qin Dynasty. Intending to impose centralized rule and prevent the resurgence of feudal lords, he ordered the destruction of the wall sections that divided his empire along the former state borders. To protect the empire against intrusions by the Xiongnu (Turks) people from the north, he ordered the building of a new wall to connect the remaining fortifications along the empire's new northern frontier. Transporting the large quantity of materials required for construction was difficult, so builders always tried to use local resources. Stones from the mountains were used over mountain ranges, while rammed earth was used for construction in the plains. There are no surviving historical records indicating the exact length and course of the Qin Dynasty walls. Most of the ancient walls have eroded away over the centuries, and very few sections remain today. Later, the Han, Sui, Northern and Jin dynasties all repaired, rebuilt, or expanded sections of the Great Wall at great cost to defend themselves against northern invaders.

The Great Wall concept was revived again during the Ming Dynasty following the Ming army's defeat by the Mongols in the Battle of Tumu in 1449. The Ming had failed to gain a clear upper-hand over the Mongols after successive battles, and the long-drawn conflict was taking a toll on the empire. The Ming adopted a new strategy to keep the Mongols out by constructing walls along the northern border of China. Acknowledging the Mongol control established in the Ordos Desert, the wall followed the desert's southern edge instead of incorporating the bend of the Huang He.

Unlike the earlier Qin fortifications, the Ming construction was stronger and more elaborate due to the use of bricks and stone instead of rammed earth. As Mongol raids continued periodically over the years, the Ming devoted considerable resources to repair and reinforce the walls. Sections near the Ming capital of Beijing were especially strengthened.

Towards the end of the Ming Dynasty, the Great Wall helped defend the empire against the Manchu invasions that began around 1600. Under the military command of Yuan Chonghuan, the Ming army held off the Manchus at the heavily fortified Shanhai Pass, preventing the Manchus from entering the Liaodong Peninsula and the Chinese heartland. The Manchus were finally able to cross the Great Wall in 1644, when the gates of Shanhai Pass were opened by Wu Sangui, a corrupt Ming border general, after being bribed. The Manchus quickly seized Beijing, and defeated the newly founded Shun Dynasty and remaining Ming resistance, to establish the Qing Dynasty.

Under Qing rule, China's borders extended beyond the walls, and Mongolia was annexed into the empire, so construction and repairs on the Great Wall were discontinued.

Characteristics
Before the use of bricks, the Great Wall was mainly built from earth, stones, and wood.

During the Ming Dynasty, however, bricks were heavily used in many areas of the wall, as were materials such as tiles, lime, and stone. The size and weight of the bricks made them easier to work with than earth and stone, so construction quickened. Additionally, bricks could bear more weight and endure better than rammed earth. Stone can hold under its own weight better than brick, but is more difficult to use. Consequently, stones cut in rectangular shapes were used for the foundation, inner and outer brims, and gateways of the wall. Battlements line the uppermost portion of the vast majority of the wall, with defensive gaps a little over 30 cm (a foot) tall, and about 23 cm (9 inches) wide.

The steps that form the Great Wall of China are very steep and tall in some areas. Tourists often become exhausted climbing the wall and walk no more than a kilometer or two (around a mile).

Condition
While some portions north of Beijing and near tourist centers have been preserved and even reconstructed, in many locations the Wall is in disrepair. Those parts might serve as a village playground or 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. No comprehensive survey of the wall has been carried out, so it is not possible to say how much of it survives, especially in remote areas. Intact or repaired portions of the Wall near developed tourist areas are often frequented by sellers of tourist kitsch.

Watchtowers and barracks
The wall also has watch towers at regular intervals, which were used to store weapons, house troops, and send smoke signals. 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.

Recognition
The wall was made as a UNESCO World Heritage Site in 1987.

Mao Zedong had a saying, "You're not a real man if you haven't climbed the Great Wall" (Bú dào Chángchéng fēi hǎo hàn). Originally this saying was used to bolster his revolution in trekking north. But over time the saying has been reduced to a promotional slogan for the Great Wall of China. In Badaling (north of Beijing) the 'real man stone' can be found with the saying engraved on it.

Lists of recommended travel destinations often feature the Great Wall of China, which also appears in several listings of seven wonders of the modern world -- including the recently announced New Seven Wonders of the World which claimed to record a 100 million votes.