United’s new Boarding Area E in Terminal 3 at San Francisco Airport has more than 375 power outlets. United Continental Holdings

The kids area at United’s new Boarding Area E at San Francisco Airport Terminal 3 features a Spirogyrate, an interactive art installation by Bay Area artist Eric Staller. United Continental Holdings

Lounge chairs are a seating option for relaxation in United’s new Boarding Area E at San Francisco Airport Terminal 3. United Continental Holdings

There are a variety of seating options in United’s new Boarding Area E at San Francisco Airport Terminal 3. United Continental Holdings

Boarding Area E offers 10 gates for United passengers. United Continental Holdings

United’s new boarding area at SFO Terminal 3 will feature a yoga room and restaurants. ABC News 7

United offered a sneak peak to the media January 25 of its new boarding area in Terminal 3 at SFO. San Francisco Airport/Paul Vilanueva

United CEO Jeff Smisek talks to the meeting at the airline’s new boarding area in Terminal 3 at San Francisco Airport. San Francisco Airport/Paul Vilanueva

An overview of the presser at United’s new boarding area at San Francisco Airport on January 25. San Francisco Airport/Paul Vilanueva

Travelers who recall the old American Airlines wing at Terminal 3 in San Francisco International Airport won’t believe what’s happened to it.

The long corridor with 10 gates featured a low, acoustic-tile ceiling with fluorescent lighting, black-and-white signs with gate numbers, and rows of those generic, black plastic-covered seats you can only find in airports. A couple of crowded restaurants and newsstands were wedged between the gates.

American moved to the new Terminal 2 in 2011, and its old space has been walled off, stripped to the foundation and studs and transformed into a new boarding area for United Airlines, which also occupies the rest of Terminal 3, at a cost of $138 million to the airport.

“We’ve provided a lot of luxury perks that you wouldn’t expect to find at an airport,” said airport director John Martin. “Maybe at a hotel.”

The new Boarding Area E — or Terminal 3E, as some have nicknamed it — is light, bright and ultramodern. It opens Tuesday. Along the main corridor, the ceiling has been raised 20 to 30 feet with plenty of natural light. At the end of the walkway, a 23-foot-tall picture window offers a panoramic view of the runways, and a dangling sculpture of giant metallic globes reflects the sunset and the bustle of the airport.

The terminal also features lounge-style seating with some chairs that swivel and some shaped like eggs — and even a few that look like a bent version of a flat person and allow travelers to recline on them.

A children’s area has no play structure or toys but an interactive art installation. “Spyrogyrate,” by Bay Area artist Eric Staller, has large lighted discs on the wall and floor that spin and change colors as people stand on them.

Like the recently remodeled Terminal 2, the new wing has a yoga room with twinkling stars on the ceiling for those seeking a little tranquillity before their flights. A collection of restaurants and retail shops with an open feel and a local flavor — including two pop-up stores that will rotate once or twice a year — will serve travelers.

“We want the passenger, the moment he steps off the plane, to feel like he’s in San Francisco — with local restaurants, local stores,” said M. Arthur Gensler Jr., founder of Gensler, the firm that designed the renovation.

The terminal also offers free Wi-Fi, 375 power outlets, nine work stations and interactive maps that enable travelers to download airport information to their phones. Near the entry, a “flight deck” features touch-screen information panels and a big-screen map that depicts the last 24 hours of flights out of SFO zipping around the world.

Even the restrooms are fancy and spacious, with natural light — there are even dressing rooms.

“SFO likes to provide four-star, five-star hotel-type restrooms,” said Judy Mosqueda, the Terminal 3 project manager.

SFO spokesman Doug Yakel said the airport originally planned a simple makeover for the boarding area but changed the plans after the popularity of the Terminal 2 remodel, which blended modern design, local food and retail and art. Martin said the overhauled boarding area “goes a step above Terminal 2.”

Next up for SFO is a remodeling of the security checkpoint at Terminal 3 to improve passenger flow. The new checkpoint will include signs that display wait times. The airport will also expand the terminal to add three gates as well as more shops and restaurants. The security improvements are expected to be completed this summer, with the expansion a year away.

Farther down the line is an overhaul of the dreary Terminal 1, which is in the same condition as the splashy new T3E was a little more than two years ago.

Michael Cabanatuan is a San Francisco Chronicle staff writer. E-mail: mcabanatuan@sfchronicle.com Twitter: @ctuan ___

Photo Credit: United's new Boarding Area E in San Francisco Airport Terminal 3 offers more than 375 power outlets. United Continental Holdings