三河吉田藩
Located between Maisaka-juku and Arai-juku, in what is now the city of Kosai, Shizuoka Prefecture, the Arai Barrier was strategically positioned on the narrow strip of land between Lake Hamana and the Pacific Ocean, and was the only checkpoint on the Tōkaidō intended for travelers both by land and by water. All travelers were required to submit to an examination of their travel permits, and taxes were levied on commercial travelers with merchandise. The checkpoint was initially managed by the , a "hatamoto" post with a revenue of 1000 "koku", who was assisted by six "yoriki" and 20 "dōshin". From 1696, the post was to be held by two men who served in alternate years; however, the position was abolished in 1702 and the Arai Barrier was thereafter managed by Yoshida Domain on behalf of the shogunate.