The Port Authority of New York and New Jersey, is a joint venture between the U.S. states of New York and New Jersey, established in 1921 through an interstate compact authorized by the United States Congress. The Port Authority oversees much of the regional transportation infrastructure, including bridges, tunnels, airports, and seaports, within the geographical jurisdiction of the Port of New York and New Jersey. This 1,500-square-mile (3,900 km²) port district is generally encompassed within a 25-mile (40 km) radius of the Statue of Liberty National Monument. The Port Authority is headquartered at 4 World Trade Center.