Bayonne Bridge ca. 1932

The Bayonne Bridge, the fourth and final bridge built by the recently-created Port Authority of New York and New Jersey, opened on November 15, 1931. It was modeled after the Sydney (Australia) Harbor Bridge, which was inspired by the Hell Gate Bridge. Its 1675-foot main span, the longest for a steel arch bridge at that time, crosses the Kill van full between Bayonne, New Jersey, and Staten Island. Other H. Amman, who designed and supervised the construction of the Bayonne Bridge, was required to span a waterway used extensively for commercial shipping and to design a bridge without towers that would obstruct shipping vessels. The result was a steel arch, entirely different from Amman's other New York bridges.

Although the Bayonne Bridge appears to compete with the Sydney Harbor Bridge in Australia, construction on the Sydney Bridge actually started five years before that of the Bayonne Bridge. However, the Bayonne was completed several months earlier than the Sydney and is 25 inches longer than its Australian counterpart. Final plans necessitated a skew bridge, built at a 58 degree angle to the water in order to make the bridge connect well with highway schemes on either end. The same gold shears used for the ribbon-cutting ceremonies opening both bridges were later separated, each host city retaining one blade. A replica of the last spike used in the arch of the Sydney Bridge was presented to the Port Authority chief.

Although the Bayonne was planned as an essential part of the regional system linking the boroughs of the City of New York and the City itself to the state of New Jersey, it began to pay for itself only when completion of the Verrazano-Narrow Bridge opened Staten Island to the development and increased usage of the Bayonne.