大(da)(da)(da)同(tong)古(gu)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)是萬里長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)的重(zhong)要(yao)(yao)組成部分(fen),主(zhu)要(yao)(yao)分(fen)布于(yu)大(da)(da)(da)同(tong)市的天(tian)鎮縣(xian)、陽高(gao)縣(xian)、新(xin)榮區(qu)、左(zuo)云縣(xian)、渾源縣(xian)、靈(ling)丘縣(xian)、廣靈(ling)縣(xian)7個縣(xian)區(qu)。大(da)(da)(da)同(tong)的長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)歷史所(suo)跨朝代(dai)較(jiao)多,現存主(zhu)要(yao)(yao)是明代(dai)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)。大(da)(da)(da)同(tong)作為(wei)(wei)當(dang)時拱衛京都(dou)的屏(ping)障,明長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)分(fen)外長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)和內(nei)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng),如今的大(da)(da)(da)同(tong)市居于(yu)內(nei)外長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)之間,南部和北(bei)部、西部的行(xing)政(zheng)區(qu)劃(hua)線大(da)(da)(da)部分(fen)以長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)為(wei)(wei)界。2009年(nian)公(gong)布的長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)資源調(diao)查(cha)數據(ju)中(zhong),大(da)(da)(da)同(tong)市境內(nei)明代(dai)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)343167米,共有長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)烽火臺、古(gu)堡(bao)(bao)等(deng)843處(chu)。1986年(nian)8月18日,大(da)(da)(da)同(tong)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)被山(shan)(shan)西省(sheng)人(ren)民政(zheng)府公(gong)布為(wei)(wei)第二(er)批省(sheng)級文物保護單位。相關的壁畫、雕刻、碑文等(deng)與長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)有直接關系的文物超過2000處(chu)。天(tian)鎮縣(xian)新(xin)平堡(bao)(bao)的玉皇(huang)閣鎮邊樓以及修在海拔1736米山(shan)(shan)頂上的樺門堡(bao)(bao),陽高(gao)縣(xian)墩臺密布的長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)鄉(xiang),新(xin)榮區(qu)拱衛北(bei)魏皇(huang)陵的方山(shan)(shan)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)和得勝堡(bao)(bao)等(deng)邊墻五堡(bao)(bao),左(zuo)云摩天(tian)嶺兩個制(zhi)高(gao)點之間的寧魯樓,靈(ling)丘牛幫口的內(nei)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)都(dou)是大(da)(da)(da)同(tong)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)的精(jing)美華章。
據《三云籌俎(zu)考·大(da)(da)(da)同(tong)總鎮(zhen)(zhen)圖說(shuo)》統計,大(da)(da)(da)同(tong)鎮(zhen)(zhen)先后(hou)修(xiu)大(da)(da)(da)邊(bian)(bian)、二邊(bian)(bian)516.3里;內(nei)(nei)(nei)(nei)五(wu)堡(bao)(bao)、外(wai)(wai)五(wu)堡(bao)(bao)、塞外(wai)(wai)五(wu)堡(bao)(bao)、云岡六堡(bao)(bao)等主要城(cheng)(cheng)(cheng)堡(bao)(bao)72座(zuo)(城(cheng)(cheng)(cheng)20,堡(bao)(bao)52);邊(bian)(bian)城(cheng)(cheng)(cheng)776個(ge);火(huo)路墩(dun)833個(ge)。在(zai)大(da)(da)(da)同(tong)明長(chang)(chang)(chang)城(cheng)(cheng)(cheng)自居庸(yong)關以西(xi)(xi)(xi)(xi)(xi),分南(nan)北(bei)(bei)兩(liang)線到山西(xi)(xi)(xi)(xi)(xi)偏關會合(he),被稱為內(nei)(nei)(nei)(nei)、外(wai)(wai)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)。外(wai)(wai)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)即(ji)居庸(yong)關西(xi)(xi)(xi)(xi)(xi)北(bei)(bei)經(jing)赤城(cheng)(cheng)(cheng)、崇禮(li)、張(zhang)家口(kou)、萬全(quan)、懷安(an)而(er)進(jin)(jin)入(ru)(ru)(ru)大(da)(da)(da)同(tong)市(shi)的(de)(de)天鎮(zhen)(zhen)、陽(yang)(yang)高(gao)(gao)、大(da)(da)(da)同(tong)、左(zuo)(zuo)(zuo)(zuo)云沿內(nei)(nei)(nei)(nei)蒙古、山西(xi)(xi)(xi)(xi)(xi)交(jiao)界處(chu),達于偏關、河(he)(he)曲;內(nei)(nei)(nei)(nei)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)從(cong)居庸(yong)關西(xi)(xi)(xi)(xi)(xi)南(nan)經(jing)河(he)(he)北(bei)(bei)易(yi)縣(xian)(xian)、渾源(yuan)、阜平(ping)而(er)進(jin)(jin)入(ru)(ru)(ru)大(da)(da)(da)同(tong)市(shi)的(de)(de)靈(ling)(ling)丘、渾源(yuan),再經(jing)應縣(xian)(xian)、繁峙、神池(chi)而(er)至(zhi)(zhi)(zhi)老營。據現存長(chang)(chang)(chang)城(cheng)(cheng)(cheng)實測(ce),外(wai)(wai)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)分別由(you)(you)懷安(an)縣(xian)(xian)桃溝(gou)村、西(xi)(xi)(xi)(xi)(xi)洋河(he)(he)鄉馬市(shi)口(kou)南(nan)北(bei)(bei)兩(liang)路進(jin)(jin)入(ru)(ru)(ru)天鎮(zhen)(zhen)縣(xian)(xian)境(jing)(jing),在(zai)新平(ping)樂村與西(xi)(xi)(xi)(xi)(xi)路長(chang)(chang)(chang)城(cheng)(cheng)(cheng)相交(jiao)。天鎮(zhen)(zhen)境(jing)(jing)內(nei)(nei)(nei)(nei)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)約(yue) 105華里,存黃土夯(hang)(hang)筑的(de)(de)墩(dun)臺61座(zuo)。由(you)(you)天鎮(zhen)(zhen)水磨口(kou)向(xiang)西(xi)(xi)(xi)(xi)(xi)三里進(jin)(jin)入(ru)(ru)(ru)陽(yang)(yang)高(gao)(gao)縣(xian)(xian)十九墩(dun)村界,至(zhi)(zhi)(zhi)鎮(zhen)(zhen)邊(bian)(bian)堡(bao)(bao)西(xi)(xi)(xi)(xi)(xi)出(chu)陽(yang)(yang)高(gao)(gao)進(jin)(jin)入(ru)(ru)(ru)大(da)(da)(da)同(tong)市(shi)區境(jing)(jing)。陽(yang)(yang)高(gao)(gao)境(jing)(jing)內(nei)(nei)(nei)(nei)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)計 100余里,現存夯(hang)(hang)土處(chu)臺 119座(zuo)。從(cong)陽(yang)(yang)高(gao)(gao)鎮(zhen)(zhen)邊(bian)(bian)堡(bao)(bao)向(xiang)西(xi)(xi)(xi)(xi)(xi)約(yue)八華里進(jin)(jin)入(ru)(ru)(ru)大(da)(da)(da)同(tong)元墩(dun)村界,經(jing)鎮(zhen)(zhen)川口(kou)、宏(hong)賜堡(bao)(bao)、鎮(zhen)(zhen)羌堡(bao)(bao),經(jing)拒(ju)墻口(kou)、拒(ju)門口(kou)、助馬口(kou)至(zhi)(zhi)(zhi)十三邊(bian)(bian),轉南(nan)至(zhi)(zhi)(zhi)磚樓溝(gou)入(ru)(ru)(ru)左(zuo)(zuo)(zuo)(zuo)云縣(xian)(xian)界。另一條(tiao)由(you)(you)宏(hong)賜堡(bao)(bao)向(xiang)西(xi)(xi)(xi)(xi)(xi)經(jing)新榮、破魯至(zhi)(zhi)(zhi)吳(wu)施窯入(ru)(ru)(ru)左(zuo)(zuo)(zuo)(zuo)云界,這道長(chang)(chang)(chang)城(cheng)(cheng)(cheng)當地(di)人稱“二道邊(bian)(bian)”。南(nan)北(bei)(bei)兩(liang)道長(chang)(chang)(chang)城(cheng)(cheng)(cheng)共(gong) 210華里。長(chang)(chang)(chang)城(cheng)(cheng)(cheng)由(you)(you)大(da)(da)(da)同(tong)磚樓向(xiang)南(nan)進(jin)(jin)入(ru)(ru)(ru)左(zuo)(zuo)(zuo)(zuo)云縣(xian)(xian)保安(an)堡(bao)(bao)地(di)界,至(zhi)(zhi)(zhi)二十邊(bian)(bian)向(xiang)西(xi)(xi)(xi)(xi)(xi)北(bei)(bei)出(chu)左(zuo)(zuo)(zuo)(zuo)云進(jin)(jin)入(ru)(ru)(ru)右玉縣(xian)(xian)界。長(chang)(chang)(chang)城(cheng)(cheng)(cheng)在(zai)左(zuo)(zuo)(zuo)(zuo)云境(jing)(jing)內(nei)(nei)(nei)(nei)長(chang)(chang)(chang)約(yue)86華里。以上這段(duan)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)在(zai)大(da)(da)(da)同(tong)市(shi)境(jing)(jing)內(nei)(nei)(nei)(nei)約(yue)長(chang)(chang)(chang) 501華里。大(da)(da)(da)同(tong)市(shi)、渾源(yuan)、靈(ling)(ling)丘縣(xian)(xian)境(jing)(jing)內(nei)(nei)(nei)(nei)的(de)(de)明長(chang)(chang)(chang)城(cheng)(cheng)(cheng)周內(nei)(nei)(nei)(nei)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)。渾源(yuan)境(jing)(jing)內(nei)(nei)(nei)(nei)計 160華里,靈(ling)(ling)丘境(jing)(jing)內(nei)(nei)(nei)(nei)長(chang)(chang)(chang)約(yue) 190華里。明內(nei)(nei)(nei)(nei)、外(wai)(wai)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)在(zai)大(da)(da)(da)同(tong)境(jing)(jing)內(nei)(nei)(nei)(nei)總長(chang)(chang)(chang)為 800多華里。為山西(xi)(xi)(xi)(xi)(xi)省重(zhong)點(dian)文物(wu)保護單位。