Upon emerging from the valley and entering the town of Marilla, NY 358 turned west onto Liberia Road and followed it to the creekside community of Porterville.

The route continued on through rural portions of Marilla to the hamlet of the same name, where it served as the primary north–south street in the community.

[3] The route continued onward into the town of Alden, where the amount of development along the highway began to increase.

It crossed over Cayuga Creek, then ended shortly afterward at an intersection with US 20 (Broadway).

[8][9] Two sections of NY 358 were transferred from the state of New York to Erie County in the 1980s as part of two separate highway maintenance swaps between the two levels of government.

[citation needed] NY 358 continued to exist until April 1982, when the designation was split into four other routes.