Two and half years after plans for the Vessel were first revealed, the sculpture saw its first first official visitors Friday — celebrities, real estate heavy hitters and Big Bird himself among them.

The 150-foot sculpture, made of interconnected stairs and landings, was unveiled as part of the official opening of Hudson Yards, the $25B megaproject from Related Cos. and Oxford Properties Group that has changed New York City's real estate landscape and had an indelible impact on its skyline.

“It’s amazing," Related CEO Jeff Blau told Bisnow after the official opening ceremony Friday morning, noting 8M SF of office space and nearly 1M SF of retail and restaurant space has now been filled. "Eleven years in the making, and to be able to stand here today and have this open is just really an incredible achievement. It’s an incredible day for New York City."

The project is the largest private development in United States history. Oxford and Related’s site runs from 10th to 12th Avenue and from 30th to 34th Street. Ultimately, it will feature 18M SF of commercial and residential space, 4,000 apartments, 100 shops and 14 acres of public space.

But some recent coverage has been scornful.

A New York Times article wrote the incentive package for the site is actually larger than the highly criticized $3B deal offered to Amazon before the tech giant pulled out of a plan to build a new headquarters in the city.

The newspaper’s architecture critic described as the Vessel — the centerpiece of the public square — as “sheathed in a gaudy, copper-cladded steel” and as “casting egregious shadows over what passes for public open space.”

New York Magazine billed the development as a “billionaire’s fantasy."

Blau said that characterization of the incentives was misleading, adding that in the wake of Amazon’s departure, elected officials and developers need to do a better job of explaining incentive packages to the public.

“I don’t think parks and subways are subsidies. That’s the role of government to encourage growth of the city,” he said, noting Related was not specifically given the tax abatements for development. “The city put those abatements in place to encourage companies to come here. Hudson Yards would not have been here today without that.”

To mark the official opening, Hudson Yards' The Shops & Restaurants were opened to invited guests on Thursday night.

Thousands of people milled through the nearly 1M SF space — with the help of lashings of alcohol and food from the culinary and beverage offerings. Lin-Manuel Miranda, Anne Hathaway, Katie Holmes, Karlie Kloss and Maggie Gyllenhaal were reportedly in attendance.

On Friday morning, real estate executives, elected officials — including Senate Minority Leader Chuck Schumer, Rep. Adriano Espaillat, Rep. Jerrold Nadler and Council Speaker Corey Johnson — joined architects, designers and celebrities for an official opening ceremony hosted by CNN’s Anderson Cooper.

The gather luminaries led the inaugural walk up the Vessel's numerous stairs. Mayor Bill de Blasio was not in attendance, although former Knicks All-Star Carmelo Anthony — who helped design the basketball court at Moinian's luxe Sky mixed-use tower closeby — made an appearance alongside Joseph Moinian.

“It’s hard to believe it’s real,” Related Chairman Stephen Ross said in his speech. “As a real estate developer you need to be optimistic by nature … This one took a lot more than that.”

Schumer, who used the opportunity to highlight the importance of the Gateway Tunnel, said that anyone worried about the future vitality of the city should look no further than the Hudson Yards development.

“I immediately knew this project would be a boon to New York City for three main reasons — jobs, jobs and jobs,” he said.

Oxford President and CEO Blake Hutcheson, whose company joined the project in 2010, said the Hudson Yards reflected a dream he had three decades ago while studying real estate at Columbia University.

“Together, in the face of unbelievable difficulty and challenges, we have taken the original dream and bettered all expectations,” he said.

At noon Friday, the doors of the shops opened to the masses. The space, reportedly 85% occupied, is home to the first ever Neiman Marcus in the city.

There is also a mix of high-end stores and digital native offerings, as well as a slew of restaurants, bars and cafes, all coming online at a time when retailers are trying to survive in a challenging environment.

“It’s beautiful, and I hope the best for it,” said Daniel Bard, who lives in Queens and came in Friday to see the new stores. “I’m going to come back and bring my credit card and go crazy."

“It’s beautiful, and I hope the best for it,” said Daniel Bard, who lives in Queens and came in Friday to see the new stores. “I’m going to come back and bring my credit card and go crazy."