The Badaling Great Wall is the best preserved and the most popular one amongst all the sections of Great Wall. It is located at Yanqing County, more than 70 kilometers northwest from the center of Beijing City. It is more than 1,000 meters (3281 ft) above sea level, and commands a strategic position for transportation and defense in ancient times. The function of Badaling Great Wall was to protect the Juyongguan Pass in the ihistory. Badaling Great Wall became a very important military strategic place since the Spring and Autumn Period (770 BC – 476 BC) and the Warring States Period (476 BC – 221 BC). Many incomplete parts of the wall were proved to be built in the Warring States Period.
The wall of Badaling has a total length of 3, 741 meters with an average height of 8 meters. The highest part is 15 meters. The total area for a tour is 19, 000 square meters. Along the wall, there are many beacon towers. Being the important structures of the massive defense system–Great Wall, they were used to transmit military message. In those pre-electricity days，probably fire and smoke were the most efficient ways for communication. One shot with one smoke meant the enemy was about 100 men; two shots with two smokes meant 500 men and three shots with three smokes meant more than 1,000 men. By this way, a message could be transmitted over more than five hundred kilometers within a few hours. The top of the wall can permit five horses to be ridden abreast. There are arched doors at the inner side of the wall with very little distance between each two doors. The arched doors lead you to the top of the wall by stone stairs.
In 1987, Badaling was listed as a ‘World Cultural heritage’ by the United Nation.