The line enters the USA across the border bridges (two parallel railroad arch-support bridges) at CP Bridge [or CP 28] (MP 75.7), where the line is double track with speed limit 60-30 past a road bridge overhead, two bridges over streets, a road bridge overhead, and crossovers, with Suspension Bridge Yard on the south side of the line, and a road bridge overhead in the yard, and heads east past a road bridge overhead, various extra tracks on the south side at the east end of the yard, on now mostly-derelict land, the Amtrak Niagara Falls station with its brick depot on a single passenger track on the north side of the line, near the crossovers at CP 84 (MP 75.1), where the speed limit drops to 60-20, dual road bridges overhead, a through girder bridge over a road, crossovers at CP 83 [or CP 25] (MP 72.7), the erstwhile Falls Junction, where a branch south to the Niagara River bank once headed south from a wye and the speed limit rises to 60-40, crossovers at CP 82 (MP 71.5), the other end of that erstwhile wye, the site of the erstwhile Erie yard on the south side of the line, a gravel facility on the north side, a road bridge overhead, crossovers and junction at CP 81 (MP 70.4/19.7), where the Lockport Branch continues eastward while the Niagara Branch, now single track, turns south on the west leg of the Tuscarora Wye, with speed limit 10 mph on the curve, past two bridges over roads, to a junction at CP 61 (MP 19.0), where the east leg of that wye trails in and the speed limit rises to 60-40 again and heads south, still single track.
There is a bridge over a road, a detector at MP 16.2 ("Field, NY"), a grade crossing, double track begins again at CP 60 (MP 14.0), and a grade crossing. There is a grade crossing, a road alongside to the west with the river beyond it, a grade crossing of an east-west street, a junction with a (still-extant) former Erie branch headed east-northeast at North Tonawanda (MP 11.0), where the speed limit falls to 40 mph, and the land on the east side of the line is derelict, and the line passes "CP 11", two grade crossings (E-W), two bridges over east-west streets and crosses a river on a through truss bridge, passes a location where an NYC branch once headed east at a wye, bridges over an east-west street that turns north west of the line, crosses another river on a through truss bridge, and turns west, bridging over a north-south street and an east-west street in the process, bridges over two north-south streets, and then south-southwest, bridging across a north-south street and then across an east-west street with parkland on the west side, past a grade crossing to MP 9.4, where the speed limit rises to 60-40 again, past dual highway bridges overhead, a line heading away to the west, a spur trailing in on the west side, a grade crossing, a grade crossing into a plant on the west side, a grade crossing, the north and south legs of a wye on the west side, a track heading away on the west side, another track on the west side, "CP 8", a rail-served industry on the east side, Woodard Avenue (MP 7.4), crossovers at CP 55 (MP 5.5), where lines to Kenmore Yard industrial tracks on the river bank head west-northwest and the line reduces to single track again, two overhead rail bridges, CP H (MP 5.1), where the Belt Line Branch trails in on the east side and there are crossovers with a CN line on the west side of the line, a detector at MP 5.0, CP F (MP 4.4), where there is another connection with that CN line and another connection with the Belt Line Branch turns away to the east, and a bridge across another river. There are various road ramps overhead, a road alongside to the west, a bridge across the river, overhead, and a road bridge overhead.
The line comes alongside the east bank of the Niagara River and then the east end of Lake Erie, turning south past MP 2.4, where the speed limit drops to 40 mph, south-southeast past MP 2.1, where the speed limit becomes 60-30, with Chicago Street Yard on the west side, southeast at MP 1.2, where the speed limit becomes 40-30, past a road bridge overhead and a pedestrian bridge overhead, turns south-southeast again, and then east-southeast, past two road bridges overhead and MP 0.7, where the speed limit rises to 60-40 again, under highway bridges at an upper level and a road bridge at a lower level, into Buffalo's Exchange Street Station (MP 0.5, platform and depot on the north side), and then passes four road bridges overhead, extra track on the south side, two road bridges overhead, and the Chicago Street Junction (MP 0.3) with the Avenue Running Track (from the southwest) to the wye junction with the Chicago Line at CP 437 (MP 437.2 on the Chicago Line).