CHICAGO (CBS) — Hundreds of people crowded into Union Station Thursday night, but they weren’t waiting for a train.

As CBS 2’s Pamela Jones reports, the crowd came to the historic train depot for the chance to move and groove with Maroon 5.

Lights flashed in front of the stately columns in the train station’s Great Hall, as Adam Levine sang the band’s hit song “Moves Like Jagger” and evoked the subject of the song with his own stage moves.

Even the band was excited about the venue.

“We usually don’t perform in train stations. I think this is the first train station we’ve played at,” said Maroon 5 lead guitarist James Valentine. “A true honor.”

“I wonder if Train has ever played at a train station,” quipped Levine.

Fans couldn’t wait to see the group, especially since the concert was free.

“I, like, almost peed my pants,” said Maroon 5 fan Elizabeth Walsh. “I literally screamed in the middle of my office, and everyone was like, ‘Shh!’”

Walsh moved to get the deal quick, along with lines of other people in Chicago who went through Pandora, Ticketmaster and other Web sites to get the free tickets.

“We’re super-excited, said fan Eric Mugler. “We just found out about the show like two hours ago. We somehow ended up being first in line.”

Sara Bareilles kicked off the concert, evoking Carole King behind the piano. Bareilles says she is a quite the fan of our fair city – mostly.

“I would move here tomorrow if it wasn’t so darn cold in the winter,” she said.

The crowd at Union Station also got to see three other concerts across the country on the big screen.

Celine Dion sang a few tunes along with a list of other artists, including Li’l Wayne and Mary J. Blige.

Casino company Caesar’s Entertainment put on the events in Chicago, New York, Los Angeles and New Orleans to promote its Total Rewards customer loyalty program.

Chicago’s own Guiliana and Bill Rancic jumped at the chance to serve as masters of ceremonies.

“We heard it’s like Maroon 5, Mariah Carey, Celine Dion Diddy, Li’l Wayne, Cee Lo Green – I mean, it’s pretty unbelievable,” Giuliana Rancic said, “so I’m very excited.”

While the event did block off a large section of Union Station, commuters say the concert didn’t cause them too much trouble.

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