Hamilton to Dayton

From New River Junction (MP 28.0), where the NS (former PRR) line to New Castle heads away north, on the west side, the former B&O Toledo line heads northeast, Two Main Tracks, CTC, maximum speed 50 mph, past the ARMCO New Miami Mill on the east side, the branch to Middletown leaving to the east at Middletown Junction, with CSX facilities in the vee of the junction, the New Miami Yard on the east side, the end of Yard Limits at MP 30.2, where the line turns east-northeast, a grade crossing, a connector from the Middletown Branch trailing in on the east side at Overpeck Junction (MP 30.4), Busenbark, the start of single track, CTC at Trent (MP 32.4), where the line turns northeast again, a road alongside to the west, a grade crossing, Trenton, with a road alongside to the west (the former Cincinnati & Lake Erie interurban right-of-way) and two grade crossings in the village, a long turn north-northeast along the west bank of the Great Miami River, past West Middletown (across the river from Middletown), with a road alongside to the east, and then northeast again, past Poast Town and the 11,250 ft. west side siding, with a grade crossing in the siding at the south end, at Carlisle (MP 44.0), where there was once a flat crossing (with a southwest quadrant connector, of which a stub remains) with an erstwhile Big Four line, and there is currently a park (Caboose Park) on the west side, with a caboose (and previously, with several), and a grade crossing north of the park.

The line turns north-northeast, past a grade crossing with S. Union Street, with the NS Dayton Line briefly alongside to the east, separating again as the former B&O remains on the west side of the Great Miami River, past Intermediate Signals at MP 48.3, a bridge over a culvert, a grade crossing, a south-facing spur to the west, the RAy Bell Memorial Bridge overhead, and Miamisburg (MP 48.9), start of a 45 mph speed restriction to MP 49.5, Whitfield, and a detector at MP 51.3, turning east along the riverbank, and then north, with a 45 mph speed restriction from MP 53.3 to MP 54.9, and just east of due north, still along the riverbank, past the start of double track, current-of-traffic (Rule D-251) at SD Cabin (MP 54.9), a 40 mph speed restriction from MP 56.9 and MP 58.3,, and a 10 mph speed restriction through Dayton, from MP 58.4 to MP 60.6.

The former Big Four line (NS Dayton District) trails in on the east side at Miami City Junction (MP 58.5), where the line turns east-northeast, past a road bridge overhead, a grade crossing at Leo Street, MC Cabin, where the erstwhile ex-PRR line from Indianapolis once trailed in on the west side, a three-span through truss bridge over the Great Miami River (MP 58.7), a location where the erstwhile PRR Lebanon line once headed away south-southeast, the former location of Dayton Union Station, on an elevated track briding over streets, including 5th Street, and Second Street (MP 60.0), where the former PRR line to Columbus heads away east-southeast (but only for a couple of miles), the current Dayton Line continues east-northeast on former Big Four track, and the former B&O Toledo line heads away north.