“居庸关”之名，早在汉代就有了，其关址及所辖范围历代不一。明代的“居庸关”，是隆庆卫（后改延庆卫）的戍守范围。据王士翘的《西关志》载，其疆城东至西水峪与黄花镇交界，西亚坚子峪口与紫荆关交界，北至土木驿与新保安交界，南至榆河驿与宛平县交界，东西长105千米，南 “Juyongguan” in the name, as early as the Han Dynasty there, its address and the scope of jurisdiction varies from generation to generation. The “Juyong Pass” of the Ming Dynasty was the area of ​​defense of Long Qing Wei (later renamed Yan Qing Wei). According to Wang Shiqiao’s “West Guanzhi” contains, its east of the city to Xishuanyu and Huanghua town at the junction of west Asia Kennedy Yukou and Bauhinia border, north to the junction of civil and new security guards, south of Yuhe Station and Wan Ping County junction, something 105 km long, south