A freeway along the I-80 corridor had been planned in 1936 and again in 1955 to provide relief along US 46 between the George Washington Bridge and the Delaware Water Gap. With the establishment of the Interstate Highway System, this planned freeway, which had been identified in some planning documents as the Bergen-Passaic Expressway, would be incorporated into I-80. The freeway was built across New Jersey in various stages from the 1960s to 1973. The westernmost four miles in New Jersey was originally a rerouting of US 611 when built; that route was later realigned back into Pennsylvania. In the 1990s, high-occupancy vehicle lanes had existed on a part of I-80 in Morris County but were opened to regular traffic due to under-use.