The highway progresses eastward as South Main Street, heading through residential homes along the Delaware River.

Continuing eastward along South Main Street, it enters Pohatcong Township where state maintenance begins.

At that point, the residential district becomes more commercial, with County Route 519 heading to the south along Third Avenue.

The route continues eastward along New Brunswick Avenue, returning to the residential portions of Pohatcong Township.

In 1915, the New Jersey established its first highway department, thus, giving funding to localities to improve their roads.