大同(tong)古長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)是(shi)萬里(li)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)的(de)(de)重要(yao)組成(cheng)部分,主(zhu)要(yao)分布(bu)于(yu)大同(tong)市(shi)的(de)(de)天(tian)鎮縣(xian)(xian)、陽高(gao)縣(xian)(xian)、新榮區(qu)(qu)、左(zuo)云(yun)縣(xian)(xian)、渾源(yuan)縣(xian)(xian)、靈丘(qiu)縣(xian)(xian)、廣靈縣(xian)(xian)7個(ge)(ge)縣(xian)(xian)區(qu)(qu)。大同(tong)的(de)(de)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)歷史所跨朝代(dai)較多,現存(cun)主(zhu)要(yao)是(shi)明代(dai)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)。大同(tong)作為(wei)(wei)當時(shi)拱衛京都(dou)的(de)(de)屏障,明長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)分外長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)和(he)內長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng),如今的(de)(de)大同(tong)市(shi)居于(yu)內外長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)之間,南部和(he)北(bei)部、西(xi)部的(de)(de)行(xing)政(zheng)區(qu)(qu)劃線大部分以(yi)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)為(wei)(wei)界。2009年(nian)公布(bu)的(de)(de)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)資源(yuan)調查(cha)數據中,大同(tong)市(shi)境內明代(dai)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)343167米(mi),共(gong)有(you)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)烽火臺(tai)(tai)、古堡(bao)等843處(chu)。1986年(nian)8月18日,大同(tong)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)被山西(xi)省人民政(zheng)府(fu)公布(bu)為(wei)(wei)第(di)二(er)批省級(ji)文(wen)物保(bao)護單(dan)位。相關(guan)的(de)(de)壁畫、雕(diao)刻、碑文(wen)等與長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)有(you)直接關(guan)系的(de)(de)文(wen)物超過2000處(chu)。天(tian)鎮縣(xian)(xian)新平(ping)堡(bao)的(de)(de)玉皇閣鎮邊樓(lou)以(yi)及(ji)修(xiu)在海拔1736米(mi)山頂上的(de)(de)樺門(men)堡(bao),陽高(gao)縣(xian)(xian)墩臺(tai)(tai)密布(bu)的(de)(de)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)鄉,新榮區(qu)(qu)拱衛北(bei)魏皇陵的(de)(de)方(fang)山長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)和(he)得勝堡(bao)等邊墻五堡(bao),左(zuo)云(yun)摩天(tian)嶺(ling)兩(liang)個(ge)(ge)制高(gao)點之間的(de)(de)寧魯樓(lou),靈丘(qiu)牛(niu)幫口的(de)(de)內長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)都(dou)是(shi)大同(tong)長(chang)(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)(cheng)的(de)(de)精美華章。
據《三(san)(san)云(yun)(yun)(yun)籌俎考·大(da)同(tong)(tong)(tong)(tong)總鎮(zhen)(zhen)圖說》統計,大(da)同(tong)(tong)(tong)(tong)鎮(zhen)(zhen)先(xian)后修大(da)邊(bian)(bian)(bian)(bian)、二邊(bian)(bian)(bian)(bian)516.3里(li);內(nei)(nei)(nei)五堡(bao)、外(wai)五堡(bao)、塞(sai)外(wai)五堡(bao)、云(yun)(yun)(yun)岡(gang)六堡(bao)等主要(yao)城(cheng)(cheng)(cheng)(cheng)堡(bao)72座(城(cheng)(cheng)(cheng)(cheng)20,堡(bao)52);邊(bian)(bian)(bian)(bian)城(cheng)(cheng)(cheng)(cheng)776個;火路(lu)墩833個。在(zai)大(da)同(tong)(tong)(tong)(tong)明(ming)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)自居庸關(guan)以西(xi)(xi)(xi)(xi),分南(nan)北(bei)(bei)兩(liang)線(xian)到山西(xi)(xi)(xi)(xi)偏關(guan)會合,被稱(cheng)(cheng)為(wei)內(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)即居庸關(guan)西(xi)(xi)(xi)(xi)北(bei)(bei)經(jing)赤城(cheng)(cheng)(cheng)(cheng)、崇禮(li)、張(zhang)家口(kou)(kou)(kou)(kou)(kou)、萬全、懷安(an)而(er)進(jin)入大(da)同(tong)(tong)(tong)(tong)市的(de)天(tian)鎮(zhen)(zhen)、陽(yang)(yang)高(gao)、大(da)同(tong)(tong)(tong)(tong)、左(zuo)云(yun)(yun)(yun)沿內(nei)(nei)(nei)蒙古、山西(xi)(xi)(xi)(xi)交界(jie)處,達于偏關(guan)、河曲;內(nei)(nei)(nei)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)從居庸關(guan)西(xi)(xi)(xi)(xi)南(nan)經(jing)河北(bei)(bei)易(yi)縣(xian)(xian)、渾源(yuan)、阜平而(er)進(jin)入大(da)同(tong)(tong)(tong)(tong)市的(de)靈丘(qiu)、渾源(yuan),再經(jing)應縣(xian)(xian)、繁峙(zhi)、神池而(er)至老營。據現存(cun)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(an)縣(xian)(xian)桃(tao)溝(gou)村、西(xi)(xi)(xi)(xi)洋河鄉馬(ma)市口(kou)(kou)(kou)(kou)(kou)南(nan)北(bei)(bei)兩(liang)路(lu)進(jin)入天(tian)鎮(zhen)(zhen)縣(xian)(xian)境(jing)(jing),在(zai)新平樂村與(yu)西(xi)(xi)(xi)(xi)路(lu)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)相交。天(tian)鎮(zhen)(zhen)境(jing)(jing)內(nei)(nei)(nei)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)約(yue) 105華里(li),存(cun)黃土夯筑的(de)墩臺61座。由天(tian)鎮(zhen)(zhen)水磨口(kou)(kou)(kou)(kou)(kou)向西(xi)(xi)(xi)(xi)三(san)(san)里(li)進(jin)入陽(yang)(yang)高(gao)縣(xian)(xian)十九墩村界(jie),至鎮(zhen)(zhen)邊(bian)(bian)(bian)(bian)堡(bao)西(xi)(xi)(xi)(xi)出陽(yang)(yang)高(gao)進(jin)入大(da)同(tong)(tong)(tong)(tong)市區境(jing)(jing)。陽(yang)(yang)高(gao)境(jing)(jing)內(nei)(nei)(nei)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)計 100余里(li),現存(cun)夯土處臺 119座。從陽(yang)(yang)高(gao)鎮(zhen)(zhen)邊(bian)(bian)(bian)(bian)堡(bao)向西(xi)(xi)(xi)(xi)約(yue)八華里(li)進(jin)入大(da)同(tong)(tong)(tong)(tong)元墩村界(jie),經(jing)鎮(zhen)(zhen)川口(kou)(kou)(kou)(kou)(kou)、宏賜(si)堡(bao)、鎮(zhen)(zhen)羌堡(bao),經(jing)拒墻口(kou)(kou)(kou)(kou)(kou)、拒門口(kou)(kou)(kou)(kou)(kou)、助(zhu)馬(ma)口(kou)(kou)(kou)(kou)(kou)至十三(san)(san)邊(bian)(bian)(bian)(bian),轉(zhuan)南(nan)至磚樓溝(gou)入左(zuo)云(yun)(yun)(yun)縣(xian)(xian)界(jie)。另一條由宏賜(si)堡(bao)向西(xi)(xi)(xi)(xi)經(jing)新榮、破魯至吳施窯入左(zuo)云(yun)(yun)(yun)界(jie),這道(dao)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)當地(di)(di)人稱(cheng)(cheng)“二道(dao)邊(bian)(bian)(bian)(bian)”。南(nan)北(bei)(bei)兩(liang)道(dao)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)共 210華里(li)。長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)由大(da)同(tong)(tong)(tong)(tong)磚樓向南(nan)進(jin)入左(zuo)云(yun)(yun)(yun)縣(xian)(xian)保安(an)堡(bao)地(di)(di)界(jie),至二十邊(bian)(bian)(bian)(bian)向西(xi)(xi)(xi)(xi)北(bei)(bei)出左(zuo)云(yun)(yun)(yun)進(jin)入右玉縣(xian)(xian)界(jie)。長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)在(zai)左(zuo)云(yun)(yun)(yun)境(jing)(jing)內(nei)(nei)(nei)長(chang)(chang)(chang)約(yue)86華里(li)。以上這段長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)在(zai)大(da)同(tong)(tong)(tong)(tong)市境(jing)(jing)內(nei)(nei)(nei)約(yue)長(chang)(chang)(chang) 501華里(li)。大(da)同(tong)(tong)(tong)(tong)市、渾源(yuan)、靈丘(qiu)縣(xian)(xian)境(jing)(jing)內(nei)(nei)(nei)的(de)明(ming)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)周內(nei)(nei)(nei)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)。渾源(yuan)境(jing)(jing)內(nei)(nei)(nei)計 160華里(li),靈丘(qiu)境(jing)(jing)內(nei)(nei)(nei)長(chang)(chang)(chang)約(yue) 190華里(li)。明(ming)內(nei)(nei)(nei)、外(wai)長(chang)(chang)(chang)城(cheng)(cheng)(cheng)(cheng)在(zai)大(da)同(tong)(tong)(tong)(tong)境(jing)(jing)內(nei)(nei)(nei)總長(chang)(chang)(chang)為(wei) 800多(duo)華里(li)。為(wei)山西(xi)(xi)(xi)(xi)省重(zhong)點文(wen)物保護單位。