Thousands of drivers pass the construction site at Tampa International Airport every day, but few get a chance to see what’s happening behind the fences surrounding one of the largest construction projects in Tampa Bay.

On Wednesday, the airport invited 10 Tampa Bay News and other members of the media inside the secure work zone for a behind-the-scenes tour of Airside D, giving the public an up-close look at the progress being made on the airport’s first new airside terminal in nearly 20 years.

The $1.52 billion project is the centerpiece of the final phase of Tampa International Airport’s long-term master plan.

When it opens in 2029, the 600,000-square-foot terminal will add 16 gates for domestic and international flights, helping the airport expand from serving about 25 million passengers each year to an anticipated 35 million annually by 2037.

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For construction crews, one of the biggest milestones is now visible.

“Coming out of the ground is the best part,” said Dan Seeley, director of construction at Tampa International Airport. “After months of working in the ground to our standing structure of steel and doing what we’re doing right now is really gratifying for the team.”

The project has entered its vertical construction phase. More than 6,200 tons of structural steel — roughly 7,400 individual steel pieces — are being assembled alongside prefabricated elevator shafts, shuttle bridges and the framework that will eventually support the terminal’s roof, glass and passenger facilities.

Seeley said the airport wanted the public to see that progress firsthand.

“We want to make sure that the team and the community sees what we are building out here,” he said. “To see it’s a great project. It’s a strong project and this is one of the best places to build in Tampa Bay.”

Although much of the Tampa Bay area has experienced drought conditions in recent months, airport officials said the dry weather has helped construction crews stay on schedule.

Kevin Curry, general superintendent for Hensel Phelps Construction, said the work is unlike a typical commercial building project.

“The thought processes that go into that too is completely different than your average hotel, condo or apartment — anything else you see around the skyline,” Curry said. “It’s a once-in-a-lifetime project. There’s not many billion-dollar projects that you’ll do.”

The scale of the project reflects that complexity.

“There are 6,200 tons of steel, 7,400-plus or minus pieces of steel that we’re putting together, on time, on schedule,” Curry said. “About 200 craft workers, almost 24 hours a day, we’re out here.”

Construction officials say that the workforce will grow dramatically over the next two years, eventually reaching between 1,500 and 2,000 workers during peak construction.

The airport says Airside D is made up of seven major construction projects taking place simultaneously. The next several years will bring steady changes as the building begins to resemble a finished terminal.

“2026 was foundations and steel,” Curry said. “2027 is going to be interiors, glass, roof and then 2028 is a lot of commission and turned things on, getting it ready for that flight in 2029.”

Seeley said the airport is also making an effort to keep the community involved as construction continues.

“We’re really pushing the envelope to try to drive the schedule forward,” he said. “We’re going to push really hard over the next couple of years and open in 2029.”

Airport officials say they plan to host additional behind-the-scenes tours every few months, allowing the public to follow the project’s progress as Tampa International’s newest terminal continues to take shape.