Despite its problems, Newark tried to remain vital in the postwar era. The city successfully persuaded Prudential and Mutual Benefit to stay and build new offices. Rutgers University-Newark, New Jersey Institute of Technology, and Seton Hall University expanded their Newark presences, with the former building a brand-new campus on a 23-acre (9 hectare) urban renewal site. The Port Authority of New York and New Jersey made Port Newark the first container port in the nation. South of the city, during the postwar era, it took over operations at Newark Liberty International Airport, now the thirteenth busiest airport in the United States.