Track fixes at Penn Station didn't become suddenly needed overnight. Years of constant use by multiple transit operators has necessitated the repairs that Amtrak is undertaking during the "summer of hell."
Take a look back at Penn Station's history and how we got to this point.
The original Penn Station opens for business. The first day for LIRR service to and from Penn is Sept. 8.
After the sale of the station's air rights, the original Penn Station is leveled so Madison Square Garden can be built atop it.
Amtrak, formed in 1971, assumes ownership and operation of Penn Station from bankrupt Conrail. The station handled about 960 trains a day that year - a record then, and about half as many as Penn handles now.
The LIRR opens its West Side Yard, the last major project to increase train capacity at Penn.
LIRR enters into a 99-year agreement with Amtrak under which it can continue operating trains out of Penn and help cover the cost of maintaining the station.
The LIRR completes a major renovation of its portion of Penn Station, including the creation of a new 34th Street entrance, widening walkways, raising the ceiling, and building the West End Concourse.
Superstorm Sandy inundates rail tunnels leading under the East River and Hudson River into Penn Station with corrosive saltwater, causing major damage.
The LIRR sets a modern annual ridership record, carrying 89.3 million people. Amtrak also sets ridership records on some routes on its Northeast Corridor, which includes New York.
After a series of major service disruptions caused by infrastructure failures, Amtrak in May announces plans to take three tracks at Penn Station out of service during the summer to replace aging track components. The track outages force the LIRR to reduce rush-hour service by 20 percent, and devise a mitigation plan that includes running extra trains, buses and ferries.