I visited the first-ever Delta One Lounge, complete with a mini spa, terrace, and full restaurant. It's as bougie as I expected.

Delta has dozens of SkyClubs across the US, and there are plenty of ways to get access, such as a paid membership, flying on a first or business-class ticket on Delta or an eligible partner, or having the right credit card.

The new Delta One lounges, which are expected to open in Los Angeles and Boston later this year, are more selective. According to Delta, same-day arriving or departing Delta One passengers and invite-only 360 members flying first class can visit.

Also allowed are those departing or connecting same-day on partner airlines in their respective business or first-class cabins. These include Air France, Korean Air, Latam, KLM, and Virgin Atlantic Airways. You can't get in by having the right credit card.

A frosted-glass room will welcome eligible travelers and direct them to the check-in desks. This is Delta's second dedicated business-class check-in, the other being at Los Angeles International Airport.

The LAX location connects to a SkyClub — which is one of its most extravagant ones, in my opinion — but the airline said it will eventually lead to its own Delta One Lounge in October.

At Wednesday's opening, customers will use whatever security line they're eligible for at New York-JFK, like PreCheck or Delta's digital ID line.

However, come fall, Delta One lounge-goers can use a private TSA security line that leads right into the lounge. Delta has a similar setup at LAX.

To its credit, American has a fast-track security line for its premium passengers flying out of its fully renovated Terminal 8 at New York-JFK, which is co-branded with Oneworld partner British Airways.

I've previously visited two of American's new Flagship lounges at JFK and United's Polaris lounge at Dulles International Airport in Washington, DC.

All are beautifully done and individually have great elements — like United's sleeping pods and restaurant and American's wine-pouring table and circular Champagne bar.

However, I like that Delta combines everything into one and tops it off with a penthouse flare and bougie finish. It's simply more extravagant with a wider variety of amenities compared.

The sit-down restaurant offers a three-course meal complete with an appetizer, main course, and dessert. There's all sorts of seating, from high-top tables to booths, and charging ports are also available.

"We haven't done anything like this before in any of our SkyClubs," Claude Roussel, VP of Delta Sky Clubs and Lounge Experience, told Business Insider. "The level of food and beverage and quality is really unlike anything you'll see, we think, at any other airport lounges."

The restaurants at United and Delta's business-class lounges are separate from their respective buffet and market areas and offer on-demand dining.

Delta's dining room felt like I was in a Manhattan skyrise, complete with gold and wood finishings, unique wall and ceiling designs, an open kitchen, and a chandelier inspired by the Brooklyn Bridge.

Delta partnered with famous New York City-based Union Square Events and Restaurant Associates, a Danny Meyer concept, for the restaurant menu.

The meal (which had five courses for the media instead of the planned three) included hamachi crudo, corn agnolotti, seared salmon, rotisserie chicken, dark chocolate souffle, and New York cheesecake.

The market and bakery host everything from salmon and flatbread to avocado toast and eggplant Parmesan. Allergies and other eating restrictions can be accommodated.

It's impossible to go hungry here.

The cold drinks on tap during the preview included things like green tea, beetroot, and flavored waters.

Staff members were available to take orders.

The half-circle bar reminds me of the equally beautiful champagne bar that is the centerpiece of American's Terminal 8 Chelsea Lounge.

Roussel said a few expensive top-shelf drinks at the Delta One Lounge, like a LOUIS XIII Cognac, will cost, but most alcohol is complimentary.

The lounge has hundreds of seating spots available, from the bar to the restaurant to the terrace to the living room, complete with loungers, couches, and soundproof booths for private calls.

There's also a smaller dining area by the buffet, and beyond that is a section designed for business travelers. Here, customers can find portable computer monitors made by the company Espresso that connect to a laptop to provide a second screen.

The Delta One Lounge's all-season terrace resembles the indoor-outdoor concept also present at its grandiose Los Angeles SkyClub.

"The sunroof will open, and it's fully conditioned, so you can be there in the middle of winter or on a beautiful spring day," Roussel said.

The best part of the terrace, though, in my opinion, is the view of the planes. I could sit there and just watch them come and go all day.

Delta's swanky new lounge offers a mini spa with three wellness services: shoulder and neck massage, hand and arm massage, and eye treatment. Roussel said the services would take about 15 minutes to keep travelers' time in mind.

Products from Grown Alchemist are available on a cart, like face and hand creams and toners.

United, by comparison, has two full sleeping pods at Dulles with beds and a door, but Roussel said Delta's JFK lounge isn't intended for transiting passengers needing a long sleep.

"We focus really on the flights going out in the afternoon, so we don't expect people wanting to come here and take three to four-hour naps," he said. "You may have a connecting passenger in the morning, but that's not the breath of our clientele."

In addition to separate restrooms, the Delta One Lounge sports giant shower rooms stocked with toiletries, towels, slippers, and robes. Staff members are available to help.

For example, Roussel pointed to the two-way closet where customers can place suits or jackets so employees can access them without opening the shower room door.

This allows them to press or iron their clothes while the traveler freshens up. United has the same design, as well as offers robes, heated towels, and toiletry products.

If you are fresh off a long-haul flight from Europe and heading for a meeting, you could shower, get your suit pressed, and have your shoes shined all in one place.

Delta said this all-inclusive experience would distinguish it as a premium airline, and Roussel described the new exclusive Delta One space as a "destination lounge."

Delta clearly knows what its most premium customers want, from the unique artwork lining the walls and spacious seating to the business-focused services like portable monitors and suit pressing.

"You might be here for four hours and start with a coffee, followed by lunch at the Brasserie and a massage in our wellness treatment, and finishing with a cocktail at the bar before you leave," Roussel said.

Delta has had a problem with its SkyClubs being overcrowded with long entry lines, prompting the airline to change who can access the lounges, including barring employees and restricting basic economy tickets.

With the opening of the new Delta One Lounge, SkyClub goers will get relief at JFK — and eventually at Los Angeles and Boston this fall.