Plano's largest neighbor has just moved in. After years of planning and constructing, the first group of Toyota North America employees walked through new doors on their first day.

WFAA got an exclusive look at the event on May 15. At the new Toyota headquarters in Plano, more than 250 wide-eyed employees took it all in.

"We've been talking about this for 3 years now, and it's finally here," said Toyota North America CEO Jim Lentz.

"Experts said this could not be done in this short of time. Realize this is one of the largest headquarters relocations in corporate American history," Lentz said.

More than 850 days later, teams from Human Resources, Information Technology, and Security have moved in. A representative tells WFAA after the May 15 event, 200 people have been added every week through December.

"No one agency can cure our mobility and congestion challenges," said one speaker.

In the meantime, Plano is working with transportation agencies trying to figure out a way to keep traffic flowing, especially in a place like Collin County that continues to burst at the seams.

"We need to shift 20 percent of our traffic involving single drivers to other forms of transportation," said Plano representative Steve Stoler.

All parties are looking at all solutions. By the end, Toyota's 4000 employees will be on campus. The campus itself is not entirely complete. There are still small construction projects happening throughout the expansive campus.

"There's enough concrete to fill 43 Olympic size pools," joked CEO Lentz.

Lentz also said there are 12 acres of glass -- the same glass you'll find on Toyota windshields. It's a vision, now reality, years in the making.