Only four states are smaller in size than New Jersey, yet New Jersey ranks ninth in the nation in population and has the highest population density of any U.S. state, facts owing in part to its proximity to both New York City and Philadelphia but also indicative of its economic importance. New Jersey is a major industrial center, an important transportation corridor and terminus, and a long-established playground for summer vacationers.
The state is noted for its output of chemicals and pharmaceuticals, machinery, and a host of other products, including electronic equipment, printed materials, and processed foods. Bayonne is the terminus of pipelines originating in Texas and Oklahoma, and there are oil refineries at Linden and Carteret. The long history of heavy industry in New Jersey has left the state with the largest inventory of U.S. Superfund sites, and industrial cleanup is an important issue in its cities.
New Jersey has been a leader in industrial research and development since the establishment in 1876 of Thomas Edison's research facility in Menlo Park. Color televison, the videotape recorder, and the liquid crystal display were invented in New Jersey corporate research labs. Today telecommunications and biotechnology are major industries in the state, and the area near Princeton has developed into a notable high-tech center. Finance, warehousing, and "big box" retailing have also become important to the state's economy, attracting corporations and shoppers and to a large extent reversing New Jersey's onetime role as a suburb for commuters to New York City and Philadelphia.
A tremendous transportation system, concentrated in the industrial lowlands, moves products and a huge volume of interstate traffic through the state. Busy highways like the Garden State Parkway and the New Jersey Turnpike are part of a network of toll roads and freeways. New Jersey is linked to Delaware and Pennsylvania by many bridges across the Delaware River. Traffic to and from New York is served by railway and subway tunnels and by the facilities of the Port Authority of New York and New Jersey—the George Washington Bridge, the Lincoln and Holland vehicular tunnels, and three bridges to Staten Island. Airports are operated by many cities, and Newark airport (controlled by the Port Authority) ranks among the nation's busiest. Shipping in New Jersey centers on the ports of the Newark Bay and New York Bay areas—notably Port Newark and Port Elizabeth—with relatively minor seagoing traffic on the Delaware as far north as Trenton.
This extensive transportation network also serves to maintain New Jersey's well-known vacation industry, reaching ocean beaches, inland lakes, forests, and mountain resort areas. Atlantic City's emergence as a casino gambling center has made it the largest visitor destination in the state.
In addition to being a center of industry, transportation, and tourism, New Jersey is a leading state in agricultural income per acre. The scrub pine area of the southern inland region is used for cranberry and blueberry culture. North of the pine belt the soil is extremely fertile and supports a variety of crops, most notably potatoes, corn, hay, peaches, and vegetables (especially tomatoes and asparagus). Dairy products, eggs, and poultry are also important. Commercial and residential expansion, however, has taken over much of the state's farmland, and New Jersey is now almost one third developed.