Woodlawn to Dykemans

From crossovers at CP 112 (MP 11.8) for the upcoming junction, the passenger station with two side platforms at Woodlawn (MP 11.9), with a street alongside to the east, and the flyover junction, where the New Haven Line turns away just north of due east, from the outer tracks, and the four-track Harlem Line continues north-northeast, with freight speed limit 25 mph through the junction, and passenger speed limit 60 mph, with local restrictions 45 mph on Track 4 (westernmost), 50 mph on track 3 (easternmost), to MP 12.1, and freight train speed limit 35 mph, with local restriction 25 mph to MP 12.1, past the flyover bridge overhead carrying the inbound track from the New Haven Line, the passenger station, with two island platforms, each with a shelter, in the cutting, at Wakefield (MP 12.6), the passenger station with two island platforms, each with a shelter, at Mount Vernon West (MP 13.2), two bridges over streets, the interlocking and 3,200 ft. eastward siding (on the west side) at CP 113 (MP 13.3), where there is a box labeled "CP 113" on the east side, extra track to the east for Maintenance-of-Way, two extra tracks on the west side,  and the passenger station with island and east side platform on five tracks, at Fleetwood (MP 14.3).

The line turns a little bit further to the northeast, past an angled road bridge overhead, a road bridge overhead, a box labeled "ML 144" to the east, crossovers reducing the number of tracks from five to three, with a speed restriction to 55/30 between MP 14.6 and MP 14.8, a through truss bridge over a river, a road bridge overhead, a bridge over a stream, the passenger station, with two side platforms on three tracks, at Bronxville (MP 15.3), a bridge over a river, the passenger station with two side platforms on three tracks at Tuckahoe (MP 16.0), a road bridge overhead, a pedestrian bridge overhead, crossovers at CP 116 (MP 16.5), with a box labeled "CP 116" to the east, the passenger station with island and east side platform on three tracks at Crestwood (MP 16.8), crossovers at CP 117 (MP 17.3), where the number of tracks reduces to two and the passenger train speed limit rises to 65 mph, with a river alongside to the east, crossovers at CP 119 (MP 18.8), where the passenger trains speed limit falls to 60 mph, a road bridge overhead, the passenger station with two side platforms and depot to the west at Scarsdale (MP 19.0), a road bridge overhead, a wooded area, a through truss bridge over a river, and MP 19.4, where the passenger train speed limit rises to 65 mph and the freight train speed limit to 40 mph.

The line turns north, in a cutting with a building labeled "B20" to the east, past a road bridge overhead, the passenger station with two side platforms and depot to the west at Hartsdale (MP 20.6), a road alongside to the east, a wooded cutting, and crossovers at CP 121 (MP 21.0), a bridge over canal locks, an arched road bridge overhead, a box labeled "SB 222" between the tracks, northeast past the passenger station at White Plains (MP 22.4), with an island platform and an east-side platform on the same track as the island, with umbrella sheds and buildings on both platforms, where the express trains make their first stop since 125th Street and there is a 35 mph speed restriction on the curve back to the north at the station, a road bridge overhead, a bridge over a road, MP 22.7, where the passenger trains speed limit falls to 50 mph, crossovers at CP 123 (MP 23.5), where the number of tracks expands, extra track on the east side through the station, the passenger station with two island platforms at North White Plains (MP 23.8), where the local trains making all the stops from Grand Central terminate and passengers can make cross-platform connections to the  Grand Central express trains that are local north of here.

There are crossovers at CP 124 (MP 23.9), with a 30/25 speed restriction and a box labeled "CP 124" on the west side, where the number of tracks reduces to two again, a four to six track maintenance yard on the east side, and a ten-track yard with maintenance buildings on the west side, for the local train stock, a 35 mph speed restriction for freights from MP 24.0 to MP 25.4, past a grade crossing, two road bridges overhead, a bridge over a stream, an embankment, a grade crossing, the passenger station with island platform and umbrella shed at Valhalla (MP 25.5), with a road bridge in the station and a 40/30 speed restriction as the line turns northwest, a cemetery to the west, MP 25.7, where the passenger train speed limit rises to 60 mph, two grade crossings, more cemetery to the west, a pond to the west at the cemetery, the passenger station with two short side platforms for Sunday service at the cemetery only, at Mount Pleasant (MP 27.2), a grade crossing, and a road bridge overhead.

The line turns north, in a wooded area, past a highway alongside to the west, two road bridges overhead, a street alongside to the east, the passenger station with island platform and umbrella shed at Hawthorne (MP 28.3), an embankment, a highway to the west, a dirt track grade crossing (for maintainers), a bridge over a stream, a bridge over a road, a cemetery to the west, a bridge over a road, crossovers, a road bridge overhead, the passenger station with island platform and umbrella shed at Pleasantville (MP 30.5), with a 40/30 speed restriction as the line turns curvily north-northeast, a road bridge overhead, a cutting, a bridge over a stream, a cutting, a highway to the west, a bridge over a stream, crossovers at CP 132 (MP 32.2), with box "233" on the west side and a 40 mph passenger train speed restriction on Track 2 (west), building "B 32" to the east, and the passenger station with island platform at Chappaqua (MP 32.4), where the passenger train speed limit rises to 75 mph.

There is a road bridge overhead, a temporary pedestrian bridge overhead (in 4/09), a grade crossing, a wooded area, two bridges over streams, a box on the east side labeled "LOC A", crossovers, a road bridge overhead, a box on the east side labeled "LOC B", the passenger station with island platform and umbrella shed, and stone depot to the east", at Mount Kisco (MP 36.6), where the passenger train speed limit falls to 60 mph and there is a local 45 mph passenger train speed restriction, a road bridge overhead, a building "B 36" to the west of the line, extra track to the west, box "CP 137" to the east, an old spur trailing in to the east, a road bridge overhead, a bridge over a stream, a wooded area, an old spur trailing in to the east, a grade crossing, a highway alongside to the west, a bridge over a stream, a road bridge overhead, a pedestrian bridge overhead, and the passenger station with island platform and umbrella shed, and brick depot to the east, at Bedford Hills (MP 39.2), where there is a 50/30 speed restriction on Track 2.

There is a building "B 39" west of the track, an embankment, a road alongside to the west, two bridges over roads, a turn to just west of due north, past a grade crossing, the passenger station with island platform and umbrella shed at Katonah (MP 41.2), where there is a 40/30 speed restriction on Track 2, a river to the east, a road bridge overhead, a bridge over a stream, a dirt track grade crossing, a turn curvily north-northeast again, crossovers at CP 143 (MP 43.3), with box "CP 143" to the east, extra track to the west, the passenger station with island platform and umbrella shed at Golden's Bridge (MP 43.7), where a line through Mahopac once left on the west side, a road bridge overhead, a lake to the west, a highway to the east, a road bridge overhead, building "B 46" to the west, a highway to the east, the passenger station with island platform and umbrella shed at Purdy's (MP 46.1), where there is a 50/30 speed restriction, a road bridge overhead, north of the station, a bridge over a river, a road alongside to the west, and a dirt track grade crossing.

The line turns just west of due north, and then north-northeast again, past a bridge over a road, the passenger station with island platform and umbrella shed at Croton Falls (MP 47.8), where there is a 40/30 speed restriction, a bridge over a road, a ledge on a hillside to the east, a bridge over a river, a bridge over an angled road, a wooded area, a bridge over a dirt road, a 50/30 speed restriction between MP 48.2 and MP 48.4, a river on the east side with a road beyond it, brick building "B 49" on the east side, a lake on the east side, a turn north with a 50/30 speed restriction from MP 51.0 to MP 51.8, the passenger station with island platform and umbrella shed at Brewster (MP 51.9), where there is a 40/30 speed restriction, MP 52.0, where the passenger train speed limit drops to 40 mph on Track 2 and 50 mph on Track 1 (east), and the freight train speed limit drops to 20 mph, a road bridge overhead, crossovers at CP 152 (MP 52.3), a spur curves away west at Putnam Junction (MP 52.4), where the other end of the loop through Mahopac once left on the west side, the Metro-North Shops on the west side, with five tracks and a building, for the stock that runs the GCT to Southeast trains and the Southeast to Wassaic trains, crossovers at CP 153 (MP 53.1), where a 20 mph speed restriction on Track 2 starts, a road bridge overhead, and the passenger station at Brewster North (Southeast), end of the electrified service from Grand Central Terminal and start of the diesel shuttle service to Wassaic, with an angled road bridge overhead to its north..

At CP 154 (MP 53.5), where there is a box "CP 154" west of the track, the speed restriction on Track 2 ends, the number of tracks reduces to one, still TCS, with passenger train speed limit 50 mph and freight train speed limit 30 mph, and the line continues north, in a wooded area with a grade crossing, and box "ML 543" on the east side, to the junction (a connection heading away on the east side) with the Beacon Line on the east side at  Dykemans, CP 155 (MP 55.3), where TCS is replaced by MBS, with passenger train speed limit 59 mph, a lake on the east side, and the through-truss bridge carrying the Beacon Line overhead at Towners.