A tunnel through which the First Canal flows. With a length of about 124 meters, the Second Tunnel is the shortest tunnel of the entire Lake Biwa Canal. There is a plaque with engraved writing by Kaoru Inoue at the entrance of the tunnel. The phrase “Jinwa Yamao Motte Yorokobi, Chiwa Mizuno Tameni Yorokobu.” means “a virtuous man being pleased by immovable mountains and a wise man being pleased by flowing water.”