NEW YORK (Reuters) - Down in a damp, cavernous space beneath the western end of New York’s Pennsylvania station, national rail operator Amtrak showed on Thursday the three tracks it will take offline for emergency repairs, outlining the complicated operation.

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New York Governor Andrew Cuomo said the coming months will be a “summer of agony” for commuters between the Empire State and New Jersey along with those riding the entire northeast rail corridor, Amtrak’s busiest and most profitable route.

Penn Station, the nation’s busiest transit hub, has suffered derailments caused by decaying infrastructure, resulting in long delays to cross the Hudson river and backing up traffic across the region.

“It is literally crumbling,” Cuomo said during a Wednesday television appearance. “It’s been underfunded for 50 years.”

Fallout from those and other troubles has prompted calls for change from governors and lawmakers of both states.

The focus of repairs is an area called “A Interlocking,” the most complex portion of the station. Here, at least 15 tracks stretch into the North River tunnels toward New Jersey and the Long Island Rail Road’s West Side Yard, with even more tracks crossing over and blending in.

While one track is slated to be repaired at first, two adjoining tracks must also be taken offline, said Mike DeCataldo, Amtrak’s vice president of operations East. These two tracks, among the Penn station’s longest, are needed to bring in materials and support services, he explained during a tour on Thursday.

Amtrak will also replace dozens of switches, sections of tracks that can be moved to allow oncoming trains to change lanes. It is also replacing sections of steel tracks, rock ballast and wood ties, some of which are encased in concrete.

“It’s complicated. We recognize how much of an inconvenience this is,” DeCataldo said over the sound of clanging train bells, the darkness punctured by red and green signal lights.

Two weeks ago, Cuomo and New Jersey Governor Chris Christie together called for a private operator to take over the station, which is owned by Amtrak and leased by NJ Transit and the Long Island Rail Road.

Cuomo on Tuesday created a task force to study whether New York State, a private operator, or the Port Authority of New York and New Jersey should try to take over Penn Station.

New Jersey Democratic state senators blasted Cuomo’s task force because it was made up only of New York politicians and developers. They said NJ Transit uses a large portion of the station and should be considered an equal partner.

Amtrak hired private infrastructure firm HNTB Corp to help with project management and technical services during the repairs.

Critics have said Amtrak should continue to limit work to nights and weekends to displace fewer commuters, but DeCataldo said it would take “years” to finish repairs that way.

“We tried to do this as rationally and responsibly as possible,” he said.