New York City has a rich history of railroads, many of which do not exist anymore. There was speculative overbuilding in the late 19th and early 20th centuries, which gave way to bankruptcies and mergers. The New York Central Railroad operated in the northeastern and midwestern United States. The railroad was formed in 1853 by the consolidation of small railroads between Albany and Buffalo. The Pennsylvania railroad was built in 1846 and served in 12 states: Illinois, Indiana, Michigan, Ohio, Kentucky, West Virginia, Pennsylvania, New York, New Jersey, Maryland, Virginia, Delaware, and Washington, DC. In 1968, The Penn Central Company was formed by the merging of New York Central and Pennsylvania Railroads. Shortly after, in the beginning of 1969, The New Haven Railroad merged as well. The Penn Central was the nation's largest corporate mergers in United States history at that time, worth about $4.5 billion with over 94,450 employees combined involved in the merger. By 1970, Penn Central operated 35% of the nation's railroad passenger service and two-thirds of the eastern United States. The railroad track reached over 16 US states and Ontario and Quebec, covering almost 20,570 miles. The Penn Central was created as a response to challenges facing northeastern railroads in the late 1960s. One challenge they faced was increased competition due to trucks, airplanes, and other railroad lines. There were constant bankruptcies and mergers of railroads because freight revenue was not high enough to maintain operation. As freight revenues declined, tracks and equipment started deteriorating due to lack of money to maintain and repair them. While railroads in other regions of the nation generated revenues from the long-distance shipment of commodities such as coal, lumber, paper and iron ore, northeastern railroads traditionally depended more on various services because of its dense population; some of these services include passenger rail service, freight service, break-bulk freight service via boxcars, and delivery of consumer goods and perishables. Some examples of the major passenger rails in New York City include Metro-North Railroad, Long Island Rail Road, Metropolitan Transportation Authority (MTA), Port Authority Trans-Hudson (PATH), New Jersey Transit, and Amtrak. Metro-North was formed in 1983 by the union of four competing railroads – the Hudson River, New York Central, New York and Harlem, and New York, New Haven and Hartford. PATH was established in 1962 to create a viable way for commuting from New Jersey to Manhattan. Grand Central Terminal was opened to the public in 1913 and was widely hailed as an architectural gem. It became the busiest train station in the country. Pennsylvania Station opened in 1910 to serve the Pennsylvania Railroad. In 1963, the old Penn Station was demolished and replaced because of the high cost of maintaining the old structure and to take advantage of air rights. The old station had been lauded as an outstanding architectural structure. In response to the demolition of Pennsylvania Station, the Landmarks Preservation Commission designated Grand Central Terminal as a landmark in 1967, thereby subject to the protection of law. This marked the beginning of landmarks protection in New York City. Although freight trains have been surpassed by trucks and airplanes, New York City still depends heavily on the rails for passenger transportation.