 At the same time, Route 35 was removed from U.S. Route 9 between South Amboy and Iselin and realigned to follow a former piece of Route 4 between South Amboy and Rahway.From the late 1950s to the mid-1970s, there were plans to build a freeway along the Route 35 corridor from Seaside Heights north into Monmouth County; the only portion that was built became part of Route 18.Route 35 was extended south to the Island Beach State Park entrance by the 1980s.