A comparison of two maps: One is the NYC subway system as it is today, the other is the NYC subway system as it is today with a squiggly line drawn over it to show the path of the IBX. The squiggly line runs in an arc from Bay Ridge in Brooklyn, moving east, and begins to arc north after Brooklyn College. At Canarsie, the line moves northwest as it roughly traces the L and M lines before ending at the 7 line in Jackson Heights.