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The Great Wall of China ,the long wall of 10,000 Li (里)" is a series of stone and earthen fortifications in China, built, rebuilt, and maintained between the 6th century BC and the 16th century to protect the northern borders of the Chinese Empire from Xiongnu attacks 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 is the wall built between 220–200 BC by the first Emperor of China, Qin Shi Huang; little of it remains; it was much farther north than the current wall, which was built during the Ming Dynasty.

The Great Wall stretches over approximately 6,400 km (4,000 miles).At its peak, the Ming Wall was guarded by more than one million men. It has been estimated that somewhere in the range of 2 to 3 million Chinese died as part of the centuries-long project of building the wall.

Before the use of bricks, the Great Wall was mainly built from Earth or Taipa, 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 (one foot) tall, and about 23 cm (9 inches) wide.