Fordham Road has more space than any other station on the Concourse Line, as it contains numerous closed stairs and passageways. The southbound island platform widens at the north end of the station to facilitate a wall that splits it half, creating two "side" platforms. The northbound island platform is like others found throughout the system. During construction of the station, the main road of Grand Concourse was diverted into an underpass below Fordham Road, while the subway tracks were placed underneath either service road; the space in between the split southbound platform is likely where the underpass dips below grade-level. The split portion of the southbound platform once had a passageway from the northernmost staircase at the Fordham Road side from the middle track to the local one. Due to security concerns, it was permanently cordoned off by a wall and employee-only door as early as April 1998.