in the 1960s. On May 1, 1971, the federally funded Amtrak took over (with a few exceptions) all intercity passenger rail service in the continental United States. The Rio Grande, with its Denver-Ogden Rio Grande Zephyr and the Southern with its Washington, D.C.–New Orleans Southern Crescent chose to stay out of Amtrak, and the Rock Island, with two intrastate Illinois trains, was too far gone to be included into Amtrak. Freight transportation continued to labor under regulations developed when rail transport had a monopoly on intercity traffic, and railroads only competed with one another. An entire generation of rail managers had been trained to operate under this regulatory regime. Labor unions and their work rules were likewise a formidable barrier to change. Overregulation, management and unions formed an "iron triangle" of stagnation, frustrating the efforts of leaders such as the New York Central's Alfred E. Perlman. In particular, the dense rail network in the Northeastern U.S. was in need of radical pruning and consolidation. A spectacularly unsuccessful beginning was the 1968 formation and subsequent bankruptcy of the Penn Central, barely two years later. 1970–present Historically, on routes where a single railroad has had an undisputed monopoly, passenger service was as spartan and as expensive as the market and ICC regulation would bear, since such railroads had no need to advertise their freight services. However, on routes where two or three railroads were in direct competition with each other for freight business, such railroads would spare no expense to make their passenger trains as fast, luxurious, and affordable as possible, as it was considered to be the most effective way of advertising their profitable freight services. The National Association of Railroad Passengers (NARP) was formed in 1967 to lobby for the continuation of passenger trains. Its lobbying efforts were hampered somewhat by Democratic opposition to any sort of rail subsidies to the privately owned railroads, and Republican opposition to nationalization of the railroad industry. The proponents were aided by the fact that few in the federal government wanted to be held responsible for the seemingly inevitable extinction of the passenger train, which most regarded as tantamount to political suicide. The urgent need to solve the passenger train disaster was heightened by the bankruptcy filing of the Penn Central, the dominant railroad in the Northeastern United States, on June 21, 1970. Under the Rail Passenger Service Act of 1970, Congress created the