New York's newest cathedral: Inside the illuminated arches of the city's latest rail terminal as it's carved deep beneath Grand Central


Buried 16 stories beneath Grand Central Terminal a new commuter rail is being blasted and tunneled out of solid bedrock as part of an audacious $15billion development that will span 14 miles throughout the city.



The grand concourse, seen at a massive eight stories high surrounded by dripping stone walls and lapping puddles, will provide more floor space than New Orleans' Superdome stadium when finished.



It is just one of three monumental projects underway beneath New York City's streets to expand what's already the nation's biggest mass transit system transporting 5 million riders a day.

But even with blasting and machinery grinding through the rock day and night, most New Yorkers are blithely unaware of the construction or the eerie underworld that includes a 160-foot cavern, miles of tunnels and watery, gravel-filled pits.

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Future gateway: New York construction workers are seen dwarfed by four tunnels easily seen running into the city's future concourse that is about five-football fields long and eight-stories high

Caverns: Contractors work among hanging light bulbs and headlamps several stories beneath midtown Manhattan where they'll complete the East Side Access project

Coverage: The workers gently rumble New Yorkers above while blasting through the bedrock to extract gravel and space said to be able to cover up all of Central Park up to one foot

Pathways: The massive project will serve more than 5 million riders a day across its additional six miles of track Progress: A tiny train car passes through tracks laid out through one tunnel, the small beginnings of something far greater and faster to come

DEVELOPMENT'S KEY FACTS

Cost: $15billion

Projected completion: 2019

THE CONCOURSE:

Eight stories high or 160-feet



Space of 70-feet by 1,800-feet long, or roughly five football fields in size

Tunneling removed enough gravel to cover Central Park (843 acres) nearly a foot deep TRANSIT ADDITIONS: Will accommodate a Grand Central stop by the Long Island Rail Road featuring eight tracks



New Second Avenue Subway line serving Upper East Side with eight new miles



Extension of the No. 7 subway line from Times Square to a new real estate development on Manhattan's Far West Side STATISTICS:

NYC's MTA transports more than 5 million daily riders with more than 1.6 billion rides per year

In comparison:

UK's London Underground transports roughly 3 million per day and 1,107 million annually



Washington, D.C.'s metro serves about 800,000 riders per day



San Francisco's Bay Area Rapid Transit serves about 400,000 riders



Down below them, engineer Michael Horodniceanu says it's an astonishing sight that gets him every time.

'I look at it and I'm in wonder, I'm in awe,' said Horodniceanu, president of capital construction for the state Metropolitan Transportation Authority.



'I feel like when I went to Rome and entered St. Peter's Basilica for the first time. ... I looked at it and said, "Wow, how did they do that?"'



In New York, they hauled out so much rocky debris from under Grand Central that it could have covered Central Park, a park of 843 acres, almost a foot deep, Horodniceanu says.



Together, the three projects will cost an estimated $15billion.



And when they're all completed, estimated for 2019, they will bring subway and commuter rail service to vast, underserved stretches of the city, particularly the far East and West sides of Manhattan.

'They'll be a game-changer for New Yorkers,' says Horodniceanu.

It will accommodate Long Island Rail Road trains that now bypass Manhattan's East Side as they roll east through Queens and straight to Pennsylvania Station on the island's West Side.

This so-called East Side Access will bring about 160,000 passengers a day from Long Island to a new station in Queens' Sunnyside neighborhood, then about five more miles to the new, eight-track Grand Central hub.



For now, the subterranean hub is a drippy, humid construction site.



The raw, dark gray walls mark the dimensions of the future concourse — eight stories high, about 70 feet wide and 1,800 feet long, or about 'five football fields, without the end zones,' Horodniceanu says.



The Federal Transit Administration is kicking in $2.7 billion toward the estimated $8.3 billion budget, with the MTA state agency covering the rest using mostly taxpayer money.

Also under construction is the Second Avenue Subway that eventually will serve Manhattan's far East Side, from Harlem to the island's southern tip.



The planned eight miles of track will open Manhattan's East Side to millions of people who now squeeze daily onto the Nos. 4, 5 and 6 subway trains running under Lexington Avenue.

Big job: These men are busy constructing a 350,000-square-foot, $8.3 billion commuter rail concourse featuring six miles of new tunnels

No comparison: The city's 468 subway stations register more than 5 million daily riders, proving other systems to be just a fraction of that amount like in Washington D.C., which sees about 800,000

Light from above: A contractor catches some natural sunlight beaming from above while working on the Second Avenue Subway construction project in New York

Mastery: When crews prepared to drill the giant new cavity under Second Avenue, they first had to freeze the ground to about minus 20 degrees so as not to destabilize the buildings above as the boring machine cut through

Work in progress: This earlier photo taken from inside shows the workers' progress made on the tunnel while hallowing it out bit-by-bit and laying it with concrete

Secret workers: Hundreds of workers are busy underground but are barely noticed by New Yorkers above

Fresh steps: A planned glass Mezzanine elevator in the Second Avenue Subway will look like this artist's impression in the planned works to ease congestion on Lexington Avenue trains

Dubbed the 'The Line That Time Forgot,' the Second Avenue Subway has been a New York City dream since the 1920s.



Then came the Great Depression and World War II, followed by lack of funds that stopped the project after several stretches of tunnel with tracks were built in the 1970s. The existing tunnels are now being incorporated into the new ones.

The first phase - 1.7 miles with stations between East 63rd and East 96th streets - is to be completed in 2016 at a cost of $4.5 billion. Funding and plans for the rest of the route are still up in the air.

Finally, there's the extension of the No. 7 subway line from Times Square to a huge new real estate development on Manhattan's Far West Side, New York's biggest besides the World Trade Center.



It's called Hudson Yards, a small urban village of high-rises, parkland, retail businesses and cultural institutions in the West 30s.

Moody's Investors Service calls this subway extension - financed through $2.1billion worth of city-issued bonds - 'a key milestone towards attracting development.'

'These are vital projects, and they'll reinforce the infrastructure of the city,' says Mitchell Moss, director of the Rudin Center for Transportation Policy and Management at New York University.



'It's not just about people going to work; the New York subway and rail systems are busy 24 hours a day, taking people shopping, to theaters, to clubs.'

The city's 468 subway stations register more than 1.6billion rides a year.



The system is used by more than 5 million daily riders. The Metro in Washington, D.C., has about 800,000, and San Francisco's Bay Area Rapid Transit has about 400,000.



In comparison internationally, UK's London Underground transports roughly 3 million per day or 1,107 million annually.

New York's three mammoth projects require creative solutions and the latest technology.



When crews prepared to drill the giant new cavity under Second Avenue, they first had to freeze the ground to about minus 20 degrees so as not to destabilize the buildings above as the boring machine cut through.



For that, aluminum tubes were inserted from the street and a special chemical solution was poured into the ground and cooled by a refrigeration plant.



The Second Avenue tunnels hold a space-age surprise: The ceilings are coated with a material once used to fireproof the space shuttle.

The new line has another major improvement. Instead of ventilation grates that allow rainwater to pour in, the new stations will be aired using enclosed cooling plants.

When Superstorm Sandy hit the city last October, floodwaters washing over the East Side did not penetrate subway construction sites.

'We're using the best technology available today, but this is really people-intensive work,' says Horodniceanu, who supervises a team of thousands of workers on any given day.

'I feel I have the most exciting job in the world,' he says. 'It's an incredible feeling to be able to build a legacy project. I hope that one day, my grandchildren will be able to say their granddad built this.'

Future: An artist's impression of the Second Avenue Subway at 46th Street in New York City, part of $15billion improvements to the subway

Out with the old: The artist's impression of the new concourse is a far cry from the average New York subway seen here