From the east end of Selkirk Yard, end of the Inbound Track, and the junctions with the Albany Secondary, to the north, and connection to the Hudson Line and Boston Line, to the east, at Selkirk Junction/CP-SK (MP 11.5), the River Line heads just west of due south, single track, Rule 261, maximum speed 30 mph, with an 18,892 ft. east-side Controlled Siding ( 30 mph on the siding), past a southeast quadrant connector from the Boston Line, trailing in on the east side, the Division Post between the Conrail Albany and Philadelphia Divisions at MP 132.2, where the maximum speed rises to 50 mph, Ravena (MP 128.8), where the line turns just east of due south, the end of the Controlled Siding at CP-128 (MP 128.6), a turn just west of due south, where the line comes alongside the west bank of the Hudson River, the start of the 11,011 ft. east-side Controlled Siding (30 mph on the siding) at CP-121 (MP 121.1), Coxsackie (MP 120.1), and the end of the Controlled Siding at CP-118 (MP 118.9).
There is a detector at "Athens" (MP 114.9), West Athens (MP 114.7), a bridge over a side river, a former crossing with the erstwhile narrow-gauge Catskill Mountain Railway, Catskill (MP 110.0), a detector at "Catskill" (MP 108.1), the start of the 8,857 ft. east-side Controlled Siding at CP-106 (MP 106.4), Alsen (MP 104.8), the end of the Controlled Siding at CP-104 (MP 104.5), a 40 mph speed restriction, from CP 104 to MP 104.0, as the line turns south, Cementon, where the line turns just west of due south, Malden-on-Hudson, where it turns south again, a detector at "Saugerties" (MP 99.1), Saugerties (MP 99.0), where it turns just west of due south, Mount Marion (MP 95.8), Lake Katrine, where it turns south again, the start of a 15,032 ft. east-side Controlled Siding at CP-90 (MP 90.5), extra track on the west side, a 35 mph speed restriction, from MP 88.8 to MP 86.4, the erstwhile Ulster & Delaware and Ontario & Western connections on the west side, the start of the Walkill Industrial Track (formerly the erstwhile New York Central line to Campbell Hall), heading away on the west side, at Kingston (MP 88.0), and the end of the Controlled Siding at CP-87 (MP 87.6).