Kanji - Kanshi

…The three were Suzuka Barrier in Ise Province, Fuwa Barrier in Mino Province, and Arachi Barrier in Echizen Province, and were located at the points where the Tokaido, Tosando, and Hokuriku Roads crossed the border from Omi Province to the neighboring provinces. According to the military defense order, soldiers, drums, and military equipment were stationed at these barriers, and the provincial governors defended them as barrier governors. In the event of disturbing events such as the illness or death of the Emperor or the retired Emperor, or the outbreak of rebellion, a strict envoy was dispatched to close the three barriers, with the aim of preventing rebels in Kyoto from fleeing to the eastern provinces and the spread of the situation. …

*Some of the terminology explanations that mention "Kanji" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…伊勢国鈴鹿関，美濃国不破関，越前国愛発（あらち）関の三つであり，おのおの東海道，東山道，北陸道が近江国から隣国に国境を越えた地点に位置した。軍防令によると，これらの関には兵士と鼓吹，軍器が置かれ，国司が関司として守固した。三関は天皇，太上天皇の病，没等の不穏な事態や，反乱が発生した際に固関使（こげんし）が派遣され閉鎖され，京における反乱者の東国逃亡，事態の波及の防止をめざした。…

※「関司」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報