User blog comment:Yountoryuu/The Wikia's SBS/@comment-3177945-20110202235206/@comment-3177945-20110203010604

there can't be only two ways to cross the red line, because in that case you would have to go to the grand line first to travel between th 4 seas, but if that is the case i'm thinking on Mariejois being a conexion of the 4 seas and grand line just like reverse mountain but being able to go forth and back, it would make real sense