The new Fulton Center wowed visitors and train riders on its first official day open to the public Monday.

"This is not one of my stops. I came specifically today because this was opening up," said Carroll Stewart, 73, of Brooklyn.

The $1.4 billion project took 10 years to complete, with time and budget overruns. But riders were taken with the sleek steel-and-glass design and the "oculus" skylight that reflects natural light deep into the complex.

Fulton Center is expected to see 300,000 riders a day.

"It's beautiful," said Aaron Weiss, 26, of Brooklyn. "It's nice to see that there's so much light that's going to come into the space because of it."

"It's like the modern Grand Central," Weiss added.

The city's newest transit hub eases transfers among nine lines -- A, C, 2, 3, 4, 5, J and Z, plus a passageway that connects to the R train at Cortlandt Street. There is also 60,000 square feet of space for shopping and dining, but the stores are vacant as the management company finds tenants over the next year.

"I thought [the stores] would be open right now," said Robbie Rosenfeld, 44, who came to Fulton Center to take photos of the hub.

"I don't have a regular commute right now," Rosenfeld said. "But if I had to pass through here, it would be really nice."