Li Zhijun, Wang Minhao
The delimitation of sea defense zones forms the basis of the spatial deployment of sea defense. During the Ming and Qing dynasties, the military defense area boundaries of the Zhoushan Islands were divided into three main levels: the boundaries of the Wei(卫) and Zhen(镇), the boundaries of the inland and outer seas, and the boundaries of the Suo(所) and Ying(营). The northern boundary of the Wei or Zhen corresponded with the provincial boundary, which was delineated by Chenqian(陈钱)to Bixia(壁下) in Ming Dynasty and by Yang Mountain(羊山) to Maji(马迹) in Qing Dynasty. The southern boundary was marked by Nantian(南田), Jiantiao(健跳), and Niutou Mountain(牛头山) in Ming Dynasty, and by the Tianhou Palace(天后宫) at the southern end of Shipu Town(石浦镇) in Qing Dynasty. The western boundary, which extended far inland during the Ming Dynasty, was divided along the coast of Zhenhai(镇海) and Xiangshan(象山) in Qing Dynasty. The boundaries between the inland and outer seas were indicated by a line that included Wuyu Mountain(五屿山), Liangtou Cave(两头洞), Changtu(长涂), Luojia Mountain(洛泇山), Taohua Mountain(桃花山), Jiancang(尖仓), Jiushan(韭山), and Tantou(檀头). There were distinct boundaries between the five garrisons of the Ming Dynasty and the five green standard armies of the Qing Dynasty. These defense boundaries often crossed district political boundaries but never crossed prefectural or provincial boundaries. The boundaries of the inland and outer seas, as well as those of the garrisons and the Suo and Ying, were determined based on defense tasks and the natural maritime environment.