Lit. camp fortress. A temporary fortification constructed on a battlefield or stopping-place by armies on the march, used during *Sengoku jidai 戦国時代. On flat land this was called hira jinjiro 平陣城 and in mountain areas yama jinjiro 山陣城. The jinjiro was surrounded by a fence of sharp stakes *saku 柵, and on flat land a moat *hori 堀 was dug and an embankment *doi 土居 built with the earth from the moat. There was one main entrance and a hidden entrance at the back. Inside were the command headquarters *honjin 本陣, soldiers quarters jinya 陣屋, a kitchen, stables, a guardhouse bansho 番所, a watch tower *seirō 井楼 and toilets. There were also sometimes shields standing in place, and entanglements rokusai 鹿砦: defenses made of felled trees with the boughs pointing outward. Despite their temporary status, some jinjiro had towers *yagura 櫓 and even walls with loopholes *sama 狭間. The jinjiro was generally a square shape, each side measuring between approximately 30 m and 40 m.