You only have to finish 1 marathon before running Boston, you just have to run it fast enough to qualify. http://www.baa.org/races/boston-marathon/participant-i

You only have to finish 1 marathon before running Boston, you just have to run it fast enough to qualify. http://www.baa.org/races/boston-marathon/participant-information/qualifying/qualifying-standards.aspx http://www.baa.org/races/boston-marathon/participant-informa... You can also get in with a charity slot without qualifying.