New York City (Penn Station) to Spuyton-Duyvil

Since some time before 1996, Amtrak trains headed to the Empire Service route have used the west-side line from Pennsylvania Station (MP 0.0) to reach the Hudson Line at Spuyten-Duyvil (on the Harlem River). The Empire Connection departs westward from Penn Station, on the south side of the line into the Hudson River Tunnels, at the crossovers at Tower A (MP 0.2), a single track, with speed limit 15-10 to MP 0.5, curving around to the north and passing over the Hudson River Tunnels in a tunnel of its own, with the speed limit rising to 25-15 at MP 0.5, emerging from the tunnel past two city streets "bridging" overhead, another tunnel, with the Javits Convention Center on the Hudson River's east bank, to the line's west, where the electrification from Penn Station ends and the former route of the west side line trails in from the southwest at the crossovers at Empire (MP 1.0), where double track, ABS, begins and the speed limit rises to 35 mph, and many city streets bridging overhead..

 The line heads north, through another tunnel to 59th Street, past CP Jervis (MP 1.5), where New York Central once had their 60th Street yard on the west side of the line, MP 2.0, where the speed limit rises to 60-30, except on the first three curves where it is 25-10,  the curve north of MP 3, where it is 35-30, and various other curves at 55-30 or 50-30, 72nd Street, where a long section in tunnel starts, with occasional gaps in the tunnel showing highway ramps and then a city park, 130th Street, after the line has emerged from the tunnel onto the river bank, with the west-side highway to the west, the location of the former NYC Manhattanville Yard on the west side of the line, two streets bridge overhead, two road bridge overhead, a street bridges overhead, 158th Street, Martha, Fort Washington, a pedestrian bridge overhead, the east approach to the George Washington Bridge overhead, street bridges overhead, the line right on the river bank, an "elevated" street overhead, and a bridge over a street.

The line reduces to single track, and the speed limit to 45-30, at Inwood (MP 9.9), with a park to the west, and crosses the Spuyten-Duyvil moveable through truss bridge over the Harlem River to the start of Metro-North ownership at MP 10.7 and the crossovers at CP 12 (MP 10.8), where it joins the three track Metro-North Hudson Line, coming west along the north bank of the Harlem River and turning north at this point with four tracks.