It crosses over the New York State Thruway (Interstate 90 or I-90) on its way into the hamlet of Warners, where it briefly follows Canton Street and crosses the CSX Transportation-owned Rochester Subdivision rail line before becoming Warners Road once again as it follows the railroad east out of the community and into the town of Camillus.

[3] The route parallels the track for roughly 2 miles (3.2 km), over which time it passes to the north of Greenlawn Memorial Park.

NY 173 continues into and through Amboy, passing a large area of tailings that was once the site of the Syracuse Municipal Airport.

The brownfields are bordered to the north by Ninemile Creek and to the south by the Old Erie Canal, both of which are traversed by NY 173 on its way into the densely populated Fairmount neighborhood of Camillus.

NY 173 continues eastward as the Seneca Turnpike, passing to the south of Community General Hospital before it enters the southernmost portion of Syracuse.

Near the midpoint of the route's 2 miles (3.2 km) stay in Syracuse, it crosses over Onondaga Creek, on the banks of which lie Faith Heritage School and Meachem Field.

Past Jamesville, the homes that had lined the highway give way to open areas to the south and large quarries to the north.

Now back in the surrounding town of Manlius, NY 173 passes south of Fayetteville–Manlius High School before entering another rural area near a point known as Eagle Village.

[3] Upon crossing the county line, NY 173 initially turns slightly eastward to follow a less pronounced northeasterly alignment.

[6][7] NY 173 was assigned as part of the 1930 renumbering of state highways in New York to the entirety of its modern alignment.