The route is divided into the following BNSF subdivisions:
Scenic subdivision from Seattle to Everett (and Wenatchee)
(mileposts from Seattle)
Seattle (King Street) passenger station (MP 0.0x), where the speed limit is 30 mph for passenger trains, 20 mph for freights, has an island platform and a main platform, serving a total of three through tracks, with two through freight tracks on the east side, the brick-built multi-storey depot with its signature clock tower on the west side, and two south-facing stub-end platforms, serving a total of four terminal tracks on the south side of the depot. A large pedestrian bridge over the tracks, connecting with the road above the retaining wall on the east side of the line, was built in 2004 for the onset of the new Sounder commuter train service. The line north from the station is Two Main Tracks (2MT), Automatic Block Signals (ABS), Occupancy Control System (OCS), and has a road bridge overhead (Jackson Street) within the station, crossovers, and another road bridge overhead, before passing into the 5,141 ft. Seattle Tunnel 17 under downtown Seattle, from South Portal (MP 0.1) to North Portal (MP 1.4), where the line is heading northwest, the speed limit falls to 20 mph even for passenger trains, there is a road bridge overhead, the signals and crossovers at North Portal, a road bridge overhead, line reaches the shore of Puget Sound, with only a street alongside to the west, an erstwhile trolley line and the various piers (including the State Ferry pier) separating the line from the water, past a Sounder platform, grade crossings at Vine St. (MP 1.57) and Clay St. (MP 1.68), a detector at MP 2.19, a grade crossing, and a road bridge overhead. An elevated roadway (SR 99) runs overhead along the line at this point, past two extra tracks on the west side, and then no street on the west side.
As the shore curves away westward, there are two spurs on the west side for the Cargill grain elevators between the line and the shore, extra track on the east side, a closed grade crossing, a road bridge overhead, crossovers at Galer Street (MP 3.2), a road bridge overhead, and a footbridge overhead, and the line turns north to MP 4 (MP 4.0), and then passes three and then two extra tracks on the east side, the ten track Interbay freight yards (Balmer Yard, MP 4.9), on the west side of the line, and Interbay locomotive shops and roundhouse on the east side of the line, with five tracks on the east side, south of the roundhouse, five tracks on the west side of the roundhouse (but east of the line), south of the turntable, and two tracks north out of the shop in a vale between two bluffs, with a road bridge overhead and still nine yard tracks to the west.
The line turns northwest, past a road bridge overhead, 23rd Avenue (MP 5.1), a pedestrian bridge overhead, MP 5.4 (MP 5.4), crossovers at "Magnetic", and a detector at MP 6.0 on track 2, turning north at the signals at Bridge 6.3 (MP 6.2), where the speed limit drops to 20 mph as it crosses the through truss drawbridge over the exit from Lake Washington and a street and single track rail line on the north side of the ship channel, and turning northwest along the shore at the signals at Ballard (MP 6.4). The line then follows the shore as it curves due north, past a road bridge overhead, a bridge over a street, a bridge over a gulley, a north-facing extra track on the west side, Intermediate Signals on a signal bridge at MP 7 (MP 7.4), a bridge over a street, and crossovers at MP 8 (MP 7.7), where the line becomes 2MT, Centralized Traffic Control (CTC), with Puget Sound immediately to the west.
The speed limit rises to 50-45, as the line turns northeast along the shore, past a detector at MP 9.7 to Metum, where it turns north again, with a low wooden retaining wall on the east side, and then passes through Kirkeek Park Beach, with a footbridge overhead to the beach, and Picnic Point Park, turning north-northwest past Intermediate Signals at Richmond Beach (MP 14.0), with a low wooden retaining wall on the east side, dual-ended extra track to the east, a street to the west, a bridge over a street, a pedestrian bridge overhead, a road bridge overhead, and additional tracks on the west side at the large tank farm at Standard Oil's Tracks (MP 15.0), and north, right on the beach again, at MP 16 (MP 15.9), where the line reduces to single track, CTC, passing West Edmonds and a detector at MP 17.1, and turning northeast past a street to the west, two extra tracks to the west, a grade crossing, a street to the west, the passenger station (brick and glass depot on the east side, with platform and shelters) at Edmonds (MP 17.6), where the speed limit rises to 60-50, the Washington State ferry slip, a grade crossing, a State Park to the west, and then water to the west again.
Two Main Tracks start again at the signals at MP 18 (MP 17.8), past a bridge over a culvert, Intermediate Signals at East Edmonds, MP 21, a low wooden retaining wall to the east, and a pedestrian crossing, and the line turns north along the shore at Meadowdale, passing a beach community on the west side, an old beached ship to the west, beach houses to the west, and Mosher, and back on the shore again, past a low wooden retaining wall to the east, a detector at MP 27.2, Whidbey Island offshore, a lighthouse area to the west, a road bridge overhead, a passenger station with two side platforms, signals and crossovers at "MP 28" (a box on the east side and signal bridge to the north)), and Mukilteo (MP 28.3), where the line and shore turn east, and the speed limit becomes to 55-50, through Mukilteo State Park, past a spur to a pier on the west side for the "Port of Everett", extra track on both sides, and the spur on the east side of the line at MP 30.1 going to the Boeing Plant.
The line and shore turn northeast, past Intermediate Signals at Howarth Park (MP 31.4), extra track on the east side, and a spur into the port to the west, to Everett Junction (MP 32.1/1784.7), where there are crossovers and the line to the Port of Everett (once used by passenger trains to Vancouver, BC) continues along Puget Sound, while the main line starts to climb the hillside to the east as the speed limit falls to 25 mph and the line reduces to single track. The erstwhile Everett passenger station (used until the Sounder station opened, further north/east) was on the hillside at MP 1783.9, and used to have platforms also on the line along the shore, at the foot of the hill directly below.
The line then turns east, past a bridge over a road, and a through girder bridge over ??, just before the tunnel, through 2,110 ft. Everett Tunnel 16 (MP 1783.3) exiting the tunnel past a road bridge overhead with a north-south street, a wide road bridge overhead with a north-south road, and curves south through Everett, past signals at Broadway (west of the west leg of the wye), an east-west road bridge overhead, a road bridge overhead, the present-day Everett passenger station, with its four-storey brick and stone depot on the south/west side of the line, a single platform to the south, a single track, and an island platform with an umbrella shed, and sidings for Sounder trains on the south/west side of the line, east/south of the depot, to a signal bridge, PA Junction (MP 1782.7), where the ex-GN line to Vancouver, BC, turns away east with a very sharp curve taking it to the north, where the Everett Yard is located, while the line to Cascade Tunnel and Wenatchee heads due south at this point, and dual road bridges overhead (I-5) within the wye.