Great Wall of China - World's Longest Wall

The Great Wall of China was built over 2,000 years ago, by Qin Shi Huangdi, the first emperor of China during the Qin (Ch'in) Dynasty (221 B.C - 206 B.C.). In Chinese the wall is called "Wan-Li Qang-Qeng" which means 10,000-Li Long Wall (10,000 Li = about 5,000 km). The Great Wall of China is a series of stone and earthen fortifications in northern China, built, rebuilt, and maintained between the 5th century BC and the 16th century to protect the northern borders of the Chinese Empire from Xiongnu attacks during various successive dynasties. Since the 5th century BC, several walls have been built that were referred to as the Great Wall.

The Great Wall stretches from Shanhaiguan in the east to Lop Nur in the west, along an arc that roughly delineates the southern edge of Inner Mongolia.  The most comprehensive archaeological survey, using advanced technologies, has recently concluded that the entire Great Wall, with all of its branches, stretches for 8,851.8 km (5,500.3 mi). This is made up of 6,259.6 km (3,889.5 mi) of sections of actual wall, 359.7 km (223.5 mi) of trenches and 2,232.5 km (1,387.2 mi) of natural defensive barriers such as hills and rivers.

  
The majestic Great Wall was built with wisdom, dedication, blood, sweat and tears. It has been estimated that somewhere in the range of two to three million Chinese died as part of the centuries-long project of building the wall.

Characteristics

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.

Nearly everyone has heard of the Great Wall of China. As one of the UNESCO World Heritage Sites in China, The Great Wall is not just a wall, but a symbol of the bravery and wisdom of the Chinese people.

 He who has not climbed the Great Wall is not a true man.- Chairman Mao

Source :- http://amazing-n-weirdworld.blogspot.in/2009/09/worlds-longest-wall-great-wall-of-china.html