From the south end of North Bergen Yard, on the east side at CP-1 (MP 1.3), where the maximum speed rises to 40 mph, the Northern Running Track and the New York, Susquehanna & Western come alongside to the west and a second track runs alongside to the east, and the junction with a crossover from the Northern Running Track, trailing in on the west side, at CP-2 (MP 2.0), the River Line continues north-northeast, single track, Rule 261, past crossovers with that second track to the east, at Bridge 4 (MP 3.1), a turn north-northwest, bridging over the Northern Running Track (former Erie), or its extension, at Granton, the end of the track on the east side at CP-5 (MP 5.8), before a movable bridge over an arm of the Hackensack River, where the maximum speed rises to 50 mph, a bridge carrying the NYS&W line from Edgewater overhead, as the line turns north, and another bridge over an arm of the Hackensack River at "Little Ferry".
The line separates from the NYS&W, to its west, at Ridgefield Park, turning north-northeast, past the start of a 16,850 ft. east-side Controlled Siding (30 mph on the siding) at CP-7 (MP 7.6), Teaneck (MP 9.0), the end of the Controlled Siding at CP-10 (MP 10.9), and West Englewood, north, past Bergenfield (MP 12.0), and Dumont (MP 12.9), north-northeast and north again, bridging over a reservoir on the Hackensack River, past Harrington Park (MP 16.0) and West Norwood, north-northeast and north again, past the border between New Jersey and New York at MP 18.8, east-northeast, to Orangeburg (MP 20.5), where there is a bridge over the former Erie line that came north from the Northern Running Track, and a detector at "Orangeburg" (MP 20.5), and curvily north, past the start of a 7,693 ft. east-side siding at CP-22 (MP 22.9) and the end of the siding at CP-24 (MP 24.4), aka West Nyack, where the maximum speed drops to 40 mph.
The line runs along the east side of a lake, heading curvily just east of due north, past Valley Cottage (MP 26.4) and Congers (MP 28.5), turning north-northwest through a tunnel beyond the end of the lake, past Haverstraw (MP 32.2), north past West Haverstraw (MP 33.3), the start of a west-side 12,195 ft. Controlled Siding (30 mph on the siding) at CP-33 (MP 33.4), with a double-ended spur on the east side within the siding, the end of the Controlled Siding at CP-35 (MP 35.8), and Tompkins Cove (MP 36.7), where it has reached the west shore of the Hudson River,and turning northeast, north-northwest past a detector at "Stoney Point" (MP 38.5), where there is extra track on the east side and bridges leading to Iona Island (MP 41.0) and departing from it.
A turn northeast, still following the river bank, brings the line to Fort Montgomery, MP 43, where the maximum speed drops to 30 mph, and a tunnel, a turn north-northeast, Highland Falls, and West Point (MP 47.3), a turn north-northwest, through a tunnel under the US Military Academy, past Cornwall-on-Hudson, where the erstwhile New York, Ontario & Western once left to head west, to Middletown, and the River Line turns northwest, and then curvily just east of due north, still following the river bank, past the start of a 16,680 ft. east-side Controlled Siding (30 mph on the siding) at CP-52 (MP 52.5), where the maximum speed rises to 45 mph, the Warex Private Crossing (MP 55.6), within the siding, the end of the Controlled Siding at CP-55 (MP 55.7), where the Newburgh Industrial Track departs from the north end of the siding, and Newburgh (MP 56.2), where an erstwhile Erie line once trailed in from the southwest.