AF Tower (Alexandria) to AY Tower (Richmond)

The NS route taken by the Crescent Limited and the Manassas VRE trains diverges on both sides at AF Tower (MP 104.3), and then the double-track, CTC, cab-signaled, 70 mph maximum speed, former-RF&P line, used by the Fredricksburg VRE trains and Amtrak trains heading for Richmond and beyond, rises up in the middle and passes over the NS track on the south side, passes three bridges over roads, a Metro line alongside to the east that bridges overhead to the west side, a bridge over a street, a wide highway bridge overhead (the Beltway), Seminary (MP 103.9), the Metro line still on the west side, and Bush Hill, and turns to the south-southwest (passenger train speed limit 65 mph on the curve at MP 103.0), past a road bridge overhead, the Metro line to the west, and the VRE station (two side platforms) at Franconia-Springfield, adjacent to the Metro station on the lines to the west. Intermodal trains are permitted 60 mph maximum, manifest freights and light engines 55 mph, coal trains, phosphate trains and sand & gravel trains 45 mph on this route.

The line now runs through a wooded area, past extra track on the west side, signals and crossovers at Newington, where a branch once headed southeast into part of Fort Belvoir, and extra track on the west side trailing in, turning southwest (passenger train speed limit 65 mph on the curve at MP 100.25) past detectors at MP 96.8, a road bridge overhead, a spur on the west side trailing in at Pohick, Intermediate Signals at Barnard, where a branch once headed west into another part of Fort Belvoir, a bridge over a stream, a road bridge overhead, south-southwest past the VRE station (east-side platform only) at Lorton, just north of the Amtrak Auto-Train terminal on the west side, a bridge over a road, a road alongside to the west, signals at Lorton (MP 92.5), where the tracks from the Auto Train Terminal trail in, Ravensworth, where an additional track starts on the east side, a bridge over a divided road, a bridge over a road, a through truss bridge over the Occoquan River, a road alongside to the west, and the VRE station (east-side platform only) at Woodbridge.

The line turns south, past the VRE station (east side platform only) at Rippon, a grade crossing, Neabsco, a bridge over a road, a footbridge overhead, Featherstone Crossing, a long bridge over ??, Intermediate Signals and detectors at CFP 84.6, another long bridge over the eponymous creek at Powell's Creek, where there are Intermediate Signals, the VRE station? at Cherry Hill, a jog southwest along the west bank of the Potomac River, a footbridge overhead, a turn south-southwest at the signals at  North Possum Point (MP 81.3), where there is an 8,010 ft. signaled siding (20 mph) and additional track on the east side, a road bridge overhead, a power plant on the east side, with a connector trailing in, signals at Possum Point (MP  79.7), where the siding ends as does the double track, north end of a long single track bridge over Quantico Creek, with speed limit 55 mph, a grade crossing, the VRE and Amtrak station (two side platforms) at Quantico (MP 79.1), where double track starts again, with the line still running along the west bank of the Potomac, a bridge over a street, and a grade crossing. 

There is a US Marine helicopter base on the east side adjacent to the Intermediate Signals at Brown Field, a road bridge overhead, a street alongside to the east, a road bridge overhead, Intermediate Signals at Waller, a dirt track grade crossing, Intermediate Signals at Wide Water, a grade crossing, crossovers at Arkendale, where the line leaves the riverbank and turns southwest, a dirt track grade crossing, a long bridge over ??, Aquia, where it turns south-southwest again, (passenger train speed limit 65 mph on the curve southwest at MP 68.25), a road bridge overhead, a bridge over a road, Intermediate Signals at Brooke, where the line is running southwest, the VRE station (east side platform only) at Brooke, a road bridge overhead, Intermediate Signals and detectors at CFP 66.6, Intermediate Signals at Ross, where the line turns south, Daffan, where it turns west-southwest, a road bridge overhead, the VRE station (east side platform only) at Leeland Road, Intermediate Signals at MP 63.3, where it turns south (passenger train speed limit 65 mph on the curve at MP 61.5), and a road bridge overhead.

At the signals at Dahlgren Junction (MP 61.1), the Dahlgren Industrial Track heads away on the east side, and the line turns west, past two north-south road bridges overhead, a deck girder bridge across the Rapahannock River (speed limit 50 mph on the easterly track, 65 mph for passenger trains on the westerly track), and a viaduct south of the river to the passenger station (two side platforms, depot to the west) at the Intermediate Signals at Fredricksburg (MP 58.8, speed limit 40 mph), where VRE services end, a bridge over a street within the platforms, a bridge over a street on the embankment through town, where an extra track (15,875 ft. signaled siding, 25 mph) starts on the east side and a line once headed west to Orange, a road bridge overhead, two extra tracks on the west side, and two spurs heading away on the west side.

The ex-RF&P turns south, past double-ended spurs on the east side, a grade crossing, extra track on the east side trailing in, and Intermediate Signals, and then southeast to signals and crossovers at Hamilton (MP 55.7), end of the siding, a road alongside to the east, and a grade crossing, southwest past Intermediate Signals on an embankment at Massaponax, and a road bridge overhead, south past signals at XR (MP 53.2), where there is a VRE railyard on the east side, and Intermediate Signals, southwest past Summit and detectors at CFP 51.5, south-southeast past a grade crossing and Intermediate Signals at Guinea, extra track on the east side, a grade crossing, Intermediate Signals at John's Crossing, a grade crossing, Woodford, Intermediate Signals at Hahn's Crossing, a grade crossing and Rixey, and south past an old tower on the west side, a road bridge overhead, signals, a spur off to a lumber yard on the east side, signals at Milford (MP 37.8), a road bridge overhead, two extra tracks on the east side trailing in, a spur curving away on the east side, a road alongside to the east, two tracks curving away, Intermediate Signals at South Milford (MP 35.8), and Intermediate Signals at Pleasant Hill (MP34.2), where there are detectors.

The line turns southwest past a grade crossing, Intermediate Signals at Penola, and a dirt track grade crossing, west past a grade crossing and Intermediate Signals at Coleman's Mill, southwest past a road bridge overhead, Intermediate Signals at Ruther Glen, a spur off to the southeast, and dual road bridges overhead, and south past Intermediate Signals at Chandler and a dirt track grade crossing to the signals and crossovers at North Doswell (MP 23.1), where a 7,880 ft. signaled siding (20 mph) on the west side starts, and signals at Doswell (MP 21.8), where the siding ends, there is a grade crossing, the former C&O passenger main line from Gordonsville makes a flat crossing from northwest to southeast (50 mph on the crossing), and there are crossovers (still at Doswell) south of the ex-C&O crossing.

There is a road bridge overhead and the ex-RF&P line edges just west of south at the Intermediate Signals at Taylorsville (MP 19.6), where there are detectors, passing a bridge over a road, a road bridge overhead, a bridge over a river, a spur trailing in from industry on the west side, Intermediate Signals at Ellett, a bridge over a road, a road bridge overhead, a dirt road grade crossing, a grade crossing at the Intermediate Signals at North Ashland, where the street running through Ashland starts (with 35 mph or 45 mph speed limits, depending on the time of day), Ashland depot on the west side in the street-running section, five grade crossings on the street running section, which ends after the fifth grade crossing, extra track on the east side, trailing in, Intermediate Signals at Langford, a grade crossing, extra track on the east side, a grade crossing, and signals and crossovers at Elmont.

There is a road bridge overhead, a grade crossing, dual road bridges overhead, a spur on the east side, Hunton, a grade crossing, detectors at MP 8.1, Glen Allen, a grade crossing, a road bridge overhead, a grade crossing, a spur curving away on the east side, and extra track to industries on the east side, before turning south again at the signals and crossovers at Laurel, and then south-southeast past a tower standing on the east side (GN?) to the Amtrak Staples Mill (Richmond) station, with two passenger tracks (3 & 4) on the west side, island and west side platforms with umbrella sheds, and prefabricated depot on the west side, just north of the railroad's Greendale location (GN, MP 4.8),  where there was once a 40 mph speed restriction for northbound trains until the lead locomotive occupied Hermitage Road grade crossing (which appears to have been replaced by an overbridge) and a road bridge overhead.

South of Dumbarton, the railroad's eight-track and then even wider Acca Yard begins on the east side of the line at North Acca ("Interlocking A"), past two road bridges overhead, track 4 ends (track 3 continues to AY), with Bryan Park Shops on the west side of the line, two road bridges overhead, and the yard ends at a signal bridge ("Interlocking B") just north of AY (MP 1.7, the former location of a tower), where the main former ACL line turns southwest and the lines into the center of Richmond continue south-southeast. Between Greendale and AY, all trains are restricted to 25 mph.