大(da)(da)(da)(da)同古(gu)長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)是萬里(li)長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)的(de)(de)(de)(de)重要(yao)組成(cheng)部(bu)(bu)(bu)分,主要(yao)分布(bu)于大(da)(da)(da)(da)同市(shi)的(de)(de)(de)(de)天鎮縣(xian)(xian)(xian)、陽(yang)高(gao)(gao)縣(xian)(xian)(xian)、新榮區(qu)、左云縣(xian)(xian)(xian)、渾源縣(xian)(xian)(xian)、靈丘縣(xian)(xian)(xian)、廣靈縣(xian)(xian)(xian)7個(ge)縣(xian)(xian)(xian)區(qu)。大(da)(da)(da)(da)同的(de)(de)(de)(de)長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)歷史所跨朝代較多,現存主要(yao)是明(ming)代長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)。大(da)(da)(da)(da)同作為當時拱衛(wei)京都的(de)(de)(de)(de)屏(ping)障,明(ming)長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)分外(wai)長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)和(he)(he)內(nei)長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng),如今(jin)的(de)(de)(de)(de)大(da)(da)(da)(da)同市(shi)居于內(nei)外(wai)長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)之間,南部(bu)(bu)(bu)和(he)(he)北部(bu)(bu)(bu)、西部(bu)(bu)(bu)的(de)(de)(de)(de)行政(zheng)區(qu)劃線(xian)大(da)(da)(da)(da)部(bu)(bu)(bu)分以長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)為界(jie)。2009年公布(bu)的(de)(de)(de)(de)長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)資源調(diao)查數據中(zhong),大(da)(da)(da)(da)同市(shi)境內(nei)明(ming)代長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)343167米,共有長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)烽火(huo)臺、古(gu)堡(bao)等843處(chu)。1986年8月18日,大(da)(da)(da)(da)同長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)被山西省人民政(zheng)府公布(bu)為第二批省級文(wen)物保護單位。相(xiang)關的(de)(de)(de)(de)壁畫(hua)、雕刻、碑文(wen)等與(yu)長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)有直(zhi)接(jie)關系的(de)(de)(de)(de)文(wen)物超過(guo)2000處(chu)。天鎮縣(xian)(xian)(xian)新平堡(bao)的(de)(de)(de)(de)玉皇閣(ge)鎮邊樓以及修在海(hai)拔1736米山頂上(shang)的(de)(de)(de)(de)樺門堡(bao),陽(yang)高(gao)(gao)縣(xian)(xian)(xian)墩臺密(mi)布(bu)的(de)(de)(de)(de)長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)鄉,新榮區(qu)拱衛(wei)北魏皇陵的(de)(de)(de)(de)方山長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)和(he)(he)得勝堡(bao)等邊墻(qiang)五(wu)堡(bao),左云摩(mo)天嶺(ling)兩個(ge)制(zhi)高(gao)(gao)點之間的(de)(de)(de)(de)寧(ning)魯樓,靈丘牛(niu)幫口的(de)(de)(de)(de)內(nei)長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)都是大(da)(da)(da)(da)同長(chang)(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)的(de)(de)(de)(de)精美(mei)華(hua)章。
據(ju)《三(san)云(yun)(yun)籌(chou)俎(zu)考(kao)·大(da)(da)(da)同(tong)(tong)(tong)(tong)總鎮(zhen)(zhen)(zhen)(zhen)圖(tu)說》統計,大(da)(da)(da)同(tong)(tong)(tong)(tong)鎮(zhen)(zhen)(zhen)(zhen)先后修大(da)(da)(da)邊(bian)(bian)、二(er)邊(bian)(bian)516.3里(li)(li)(li)(li)(li)(li);內(nei)(nei)(nei)(nei)五(wu)堡(bao)、外(wai)五(wu)堡(bao)、塞(sai)外(wai)五(wu)堡(bao)、云(yun)(yun)岡六(liu)堡(bao)等主要(yao)城(cheng)(cheng)(cheng)(cheng)堡(bao)72座(zuo)(城(cheng)(cheng)(cheng)(cheng)20,堡(bao)52);邊(bian)(bian)城(cheng)(cheng)(cheng)(cheng)776個;火路墩(dun)833個。在(zai)大(da)(da)(da)同(tong)(tong)(tong)(tong)明(ming)(ming)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)自居庸(yong)關(guan)(guan)以西(xi)(xi)(xi)(xi)(xi),分南(nan)(nan)(nan)北(bei)兩(liang)線到山(shan)西(xi)(xi)(xi)(xi)(xi)偏(pian)關(guan)(guan)會合,被稱為(wei)內(nei)(nei)(nei)(nei)、外(wai)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)。外(wai)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)即居庸(yong)關(guan)(guan)西(xi)(xi)(xi)(xi)(xi)北(bei)經(jing)(jing)赤城(cheng)(cheng)(cheng)(cheng)、崇禮(li)、張家口(kou)、萬(wan)全、懷安而進(jin)(jin)(jin)(jin)入(ru)大(da)(da)(da)同(tong)(tong)(tong)(tong)市(shi)(shi)的(de)(de)天(tian)鎮(zhen)(zhen)(zhen)(zhen)、陽(yang)高(gao)、大(da)(da)(da)同(tong)(tong)(tong)(tong)、左(zuo)云(yun)(yun)沿內(nei)(nei)(nei)(nei)蒙(meng)古、山(shan)西(xi)(xi)(xi)(xi)(xi)交界(jie)(jie)處,達于偏(pian)關(guan)(guan)、河曲;內(nei)(nei)(nei)(nei)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)從(cong)居庸(yong)關(guan)(guan)西(xi)(xi)(xi)(xi)(xi)南(nan)(nan)(nan)經(jing)(jing)河北(bei)易縣(xian)(xian)(xian)、渾(hun)源、阜平而進(jin)(jin)(jin)(jin)入(ru)大(da)(da)(da)同(tong)(tong)(tong)(tong)市(shi)(shi)的(de)(de)靈丘、渾(hun)源,再經(jing)(jing)應縣(xian)(xian)(xian)、繁峙、神池而至(zhi)(zhi)老營。據(ju)現存長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)實測,外(wai)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)分別由懷安縣(xian)(xian)(xian)桃(tao)溝村、西(xi)(xi)(xi)(xi)(xi)洋河鄉馬市(shi)(shi)口(kou)南(nan)(nan)(nan)北(bei)兩(liang)路進(jin)(jin)(jin)(jin)入(ru)天(tian)鎮(zhen)(zhen)(zhen)(zhen)縣(xian)(xian)(xian)境(jing),在(zai)新(xin)平樂村與西(xi)(xi)(xi)(xi)(xi)路長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)相交。天(tian)鎮(zhen)(zhen)(zhen)(zhen)境(jing)內(nei)(nei)(nei)(nei)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)約 105華(hua)(hua)(hua)里(li)(li)(li)(li)(li)(li),存黃土夯筑(zhu)的(de)(de)墩(dun)臺61座(zuo)。由天(tian)鎮(zhen)(zhen)(zhen)(zhen)水磨(mo)口(kou)向(xiang)西(xi)(xi)(xi)(xi)(xi)三(san)里(li)(li)(li)(li)(li)(li)進(jin)(jin)(jin)(jin)入(ru)陽(yang)高(gao)縣(xian)(xian)(xian)十(shi)(shi)(shi)九墩(dun)村界(jie)(jie),至(zhi)(zhi)鎮(zhen)(zhen)(zhen)(zhen)邊(bian)(bian)堡(bao)西(xi)(xi)(xi)(xi)(xi)出(chu)陽(yang)高(gao)進(jin)(jin)(jin)(jin)入(ru)大(da)(da)(da)同(tong)(tong)(tong)(tong)市(shi)(shi)區境(jing)。陽(yang)高(gao)境(jing)內(nei)(nei)(nei)(nei)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)計 100余里(li)(li)(li)(li)(li)(li),現存夯土處臺 119座(zuo)。從(cong)陽(yang)高(gao)鎮(zhen)(zhen)(zhen)(zhen)邊(bian)(bian)堡(bao)向(xiang)西(xi)(xi)(xi)(xi)(xi)約八華(hua)(hua)(hua)里(li)(li)(li)(li)(li)(li)進(jin)(jin)(jin)(jin)入(ru)大(da)(da)(da)同(tong)(tong)(tong)(tong)元(yuan)墩(dun)村界(jie)(jie),經(jing)(jing)鎮(zhen)(zhen)(zhen)(zhen)川(chuan)口(kou)、宏賜堡(bao)、鎮(zhen)(zhen)(zhen)(zhen)羌堡(bao),經(jing)(jing)拒墻口(kou)、拒門口(kou)、助馬口(kou)至(zhi)(zhi)十(shi)(shi)(shi)三(san)邊(bian)(bian),轉南(nan)(nan)(nan)至(zhi)(zhi)磚樓(lou)溝入(ru)左(zuo)云(yun)(yun)縣(xian)(xian)(xian)界(jie)(jie)。另一條(tiao)由宏賜堡(bao)向(xiang)西(xi)(xi)(xi)(xi)(xi)經(jing)(jing)新(xin)榮、破魯至(zhi)(zhi)吳(wu)施窯入(ru)左(zuo)云(yun)(yun)界(jie)(jie),這道(dao)(dao)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)當地(di)人稱“二(er)道(dao)(dao)邊(bian)(bian)”。南(nan)(nan)(nan)北(bei)兩(liang)道(dao)(dao)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)共 210華(hua)(hua)(hua)里(li)(li)(li)(li)(li)(li)。長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)由大(da)(da)(da)同(tong)(tong)(tong)(tong)磚樓(lou)向(xiang)南(nan)(nan)(nan)進(jin)(jin)(jin)(jin)入(ru)左(zuo)云(yun)(yun)縣(xian)(xian)(xian)保(bao)安堡(bao)地(di)界(jie)(jie),至(zhi)(zhi)二(er)十(shi)(shi)(shi)邊(bian)(bian)向(xiang)西(xi)(xi)(xi)(xi)(xi)北(bei)出(chu)左(zuo)云(yun)(yun)進(jin)(jin)(jin)(jin)入(ru)右(you)玉縣(xian)(xian)(xian)界(jie)(jie)。長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)在(zai)左(zuo)云(yun)(yun)境(jing)內(nei)(nei)(nei)(nei)長(chang)(chang)(chang)約86華(hua)(hua)(hua)里(li)(li)(li)(li)(li)(li)。以上這段長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)在(zai)大(da)(da)(da)同(tong)(tong)(tong)(tong)市(shi)(shi)境(jing)內(nei)(nei)(nei)(nei)約長(chang)(chang)(chang) 501華(hua)(hua)(hua)里(li)(li)(li)(li)(li)(li)。大(da)(da)(da)同(tong)(tong)(tong)(tong)市(shi)(shi)、渾(hun)源、靈丘縣(xian)(xian)(xian)境(jing)內(nei)(nei)(nei)(nei)的(de)(de)明(ming)(ming)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)周內(nei)(nei)(nei)(nei)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)。渾(hun)源境(jing)內(nei)(nei)(nei)(nei)計 160華(hua)(hua)(hua)里(li)(li)(li)(li)(li)(li),靈丘境(jing)內(nei)(nei)(nei)(nei)長(chang)(chang)(chang)約 190華(hua)(hua)(hua)里(li)(li)(li)(li)(li)(li)。明(ming)(ming)內(nei)(nei)(nei)(nei)、外(wai)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)在(zai)大(da)(da)(da)同(tong)(tong)(tong)(tong)境(jing)內(nei)(nei)(nei)(nei)總長(chang)(chang)(chang)為(wei) 800多華(hua)(hua)(hua)里(li)(li)(li)(li)(li)(li)。為(wei)山(shan)西(xi)(xi)(xi)(xi)(xi)省重點文物保(bao)護(hu)單位。