Gubeikou Great Wall
Stretching more than 40 kilometers (25 miles), the Gubeikou Section of The Great Wall has 14 beacon towers, 143 watch towers, 16 Strategic passes, and 3 citadels. This section occupies a strategically important section. It is located 100 kilometers (62 miles) from Beijing between the Shanghaiguan and Juyongguan Sections.
The Gubeikou Section was originally built during the Northern Qi Dynasty (550-557) and was upgraded considerably during the early Ming Dynasty (1368-1644) by General Xuda. He built a stone wall along the original making the Gubeikou Section unique because it is double-lined.