Newark Liberty International Airport (IATA: EWR, ICAO: KEWR, FAA LID: EWR), originally Newark Metropolitan Airport and later Newark International Airport, is an international airport straddling the boundary between the cities of Newark and Elizabeth in Essex County and Union County, New Jersey. It is one of the major airports of the New York metropolitan area. The airport is currently owned jointly by the cities of Elizabeth and Newark and leased to and operated by the Port Authority of New York and New Jersey.Newark Airport is located 3 miles (4.8 km) south of Downtown Newark, and 9 miles (14 km) west-southwest of the borough of Manhattan. It is one of three major airports serving the New York metropolitan area; the others are John F. Kennedy International Airport and LaGuardia Airport, which are also operated by the Port Authority. Sandwiched between Interstate 95 and Interstate 78 (both components of the New Jersey Turnpike), as well as U.S. Routes 1 and 9, the airport handles more flights (though not as many passengers) than John F. Kennedy International Airport (JFK), despite being 40 percent of JFK's land size. The City of Newark built the airport on 68 acres (28 ha) of marshland in 1928 and the Army Air Corps operated the facility during World War II. After the Port Authority took it over in 1948, an instrument runway, a terminal building, a control tower and an air cargo center were added. The airport's original 1935 central terminal building is a National Historic Landmark. EWR employs more than 24,000 people.In 2017, EWR was the sixth busiest airport in the United States by international passenger traffic and fifteenth busiest airport in the country. It served 43,393,499 passengers in 2017, which made EWR the forty-third busiest airport in the world by passenger traffic. In 2019, the airport saw 46,336,452 passengers, the most in its history. Newark serves 50 carriers and is the third-largest hub for United Airlines, the airport's largest tenant (operating in all three of Newark's terminals), and FedEx Express, its second-largest tenant (operating in three buildings on two million square feet of airport property). During the 12-month period ending in July 2014, over 68% of all passengers at the airport were carried by United Airlines.