Speak of the martial defence project with Chinese great ancient time, the Great Wall should belong to the first place. And the history that date from Great Wall appears, the Great Wall that place of period of Qin Shi emperor builds is not the earliest Great Wall. Concerned research makes clear, the Hunan Great Wall of period of age the Warring States, it is China's earliest Great Wall. (a photography / Shui Xiaojie)Place of solid of class of person of the Eastern Han Dynasty writes " annals of geography of Chinese book · " in have such character: "Leaf, hunan Xie Gongyi, great Wall date says square city. " means Hunan Great Wall is called square city the earliest. In " history write down " , " mandarin " , " plan of the Warring States " and of Li Daoyuan " water classics is noted " the form that Hunan Great Wall can discover in waiting for relevant composing. As a result of the change of historical changes and landforms, hunan Great Wall discovers hard in the sign of the ground, researcher often needs to head for the road that does not have a road to undertake making an on-the-spot investigation. The Henan that the place that builds the impregnable bulwark at first is now saves county of Nanyang city northward city, later the need according to the war, begin to build the impregnable bulwark to each direction gradually, form to pour U word structure. The research work difficulty of Hunan Great Wall is very great, investigate its reason is it and common Great Wall are having those who differ to build a characteristic. Archaeologist saves limits in Henan only inside make an on-the-spot investigation, with respect to discovery on 1000 doubt are like the building of relics of Hunan Great Wall. The expert that pursues research of Hunan Great Wall thinks, the characteristic of Hunan Great Wall is with the row the city is a foundation, with ancient course pass attachs most importance to a dot, join the martial project of the knot with mountain ridge photograph. It is not the endless lofty city in traditional impression, resemble each mountain fastness however, supplement each other with hill body and dangerous place, use relief landforms to have defence. Of the city wall build, use a bit the hill danger wall of classics treatment, or use hill danger to build defense line directly, reflected adequately " with make stuff nearly " principle. As the development that studies to Hunan Great Wall, believe to be in before long in the future, the veil with Hunan mysterious Great Wall can be opened surely.