The Sanzu River (Japanese: 三途の川 Hepburn: Sanzu-no-kawa), or River of Three Crossings, is a mythological river in Japanese Buddhist tradition similar to the Hindu concept of the Vaitarna and Greek concept of the Styx.[1] Before reaching the afterlife, the souls of the deceased must cross the river by one of three crossing points: a bridge, a ford, or a stretch of deep, snake-infested waters.[2] The weight of one's offenses while alive determines which path an individual must take. It is believed that a toll of six mon must be paid before a soul can cross the river, a belief reflected in Japanese funerals when the necessary fee is placed in the casket with the dead.[3]
-Source : Wikipedia