New York’s long-delayed plan to bring Long Island Rail Road trains to Grand Central Terminal was finally realized on Wednesday, capping a project that’s as old as the MTA itself.

Just after 11 a.m., Gov. Kathy Hochul and hundreds of riders arrived aboard the first passenger train into Grand Central Madison, a terminal located 150 feet beneath the rail hub.

The station opened as a truncated shuttle service from Jamaica Terminal with only one or two trains per hour. MTA officials said full service will launch in at least three weeks, when up to 24 trains will serve the new station per hour.

“This has been a phenomenal accomplishment to get this project done,” said Hochul. “This took a long, long time. It’s been nearly 110 years to the day since the last major rail terminal [opened] in our state.”

Hochul, MTA Chairman Janno Lieber and former Gov. Andrew Cuomo promised for years to finish the project — formerly known as East Side Access — by the end of 2022. But a last-minute problem with the station’s air circulation pushed back its opening by 25 days.

The first train passengers snapped photos of the brand new Grand Central Madison terminal.

It was another delay for the project, which was one of the more notoriously mismanaged public works projects in the city’s history. The MTA in the late 1990s estimated its cost at $2.8 billion — with a construction timeline of 10 years. The price tag grew to $6.3 billion in 2006, the year the federal government agreed to pay $2.6 billion for the work, marking the largest public grant for a mass transit project in U.S. history.

But as construction delays piled up, so did the price. Federal records show the final price tag is $11.6 billion, which includes future plans to purchase additional train cars for the service.

“It’s so exciting,” said Kelly Curtain from Point Lookout in Long Island, who took the first train into the station. “As someone who’s taken the Long Island Rail Road for more than 20 years — my father took it for 45 years — this is history in the making.”

The plan to bring LIRR trains to the East Side through a new river tunnel dates back to 1968, when the MTA was formed under former Gov. Nelson Rockefeller.

The tunnel between East 63rd Street and Queens was dug in the 1970s, but work came to a halt due to the city’s financial crisis. In the 1980s, the MTA restarted work on the upper level of the tunnel, which now carries F line subway trains between Queens and Manhattan.

But the tunnel’s lower level — designed to carry LIRR trains — remained empty. Former Gov. George Pataki announced plans to revive the program in the 1990s to give Long Islanders an alternative to Penn Station.

With the terminal finally open, LIRR riders heading to the East Side could save up to 40 minutes of commuting time a day, according to the MTA.

The MTA estimates LIRR riders heading to the East side could save up to 40 minutes of commuting time a day thanks to the new terminal.

“We love Grand Central,” said Lieber. “It is the temple of mass transit. And now it has a new chapel.”

Riders must navigate a labyrinth of hallways and escalators for more than 10 minutes to get from the street to the stations’ platforms, which are 15 stories underground. “I would use that time as meditation time,” Hochul suggested.

One of the escalators to a platform stopped working less than two hours after the station opened. Thomas Fiscoe, a 36-year-old Brooklynite, said he was on the escalator when it broke down.

"I am hopeful that they don't have too many other hiccups," said Fiscoe.

The new terminal has no bathrooms or sitting areas on the platforms. The MTA built retail space in the station, but the storefronts were vacant on its opening day.

The MTA also commissioned two mosaics for the shiny new terminal by artists Yayoi Kusama and Kiki Smith.

New LIRR schedules will split the railroad’s service between Penn Station and Grand Central Madison. MTA officials said LIRR service will see a 40% boost once the new schedules take effect.

Until then, LIRR riders must transfer at Jamaica Terminal to ride into Grand Central Madison. The shuttle service will operate between 6:15 a.m. and 8 p.m. on weekdays and 7 a.m. to 11 p.m. on weekends. LIRR trains will run every 30 minutes during off-peak hours, and once per hour during peak commuting time.

John Colucci, 36, said he’s looking forward to avoiding Penn Station during his commute from Bay Shore.

“It’s awesome they let us Long Islanders into the nicer of the two stations,” he said. “It’s going to be surreal walking up into Grand Central Terminal.”