Thousands of fans braved 100 degree weather over the weekend for the New York stop of the Vans Warped Tour, where headliners including Gym Class Heroes, 3OH!3 and A Day To Remember performed to sweaty but energetic crowds.

Girls clad in bikinis and boys in nothing but shorts filled the Nassau Coliseum on Saturday (July 23), bodies decorated with neon paint and "free hugs" scribbled across stomachs.

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Five bands kicked the show off between 11 a.m. and noon on Saturday, and after running to the Vans inflatable to check out the set times, the audience rushed to watch Simple Plan play on its first major stateside tour in the past few years.

Video: Simple Plan's "Addicted"/"I'd Do Anything," Uniondale, N.Y., July 23

As the day went on and shows continued at all seven stages, every inch of shade in the venue was packed as kids braved the heat, downing free water from the trucks that tour founder Kevin Lyman had hired after seeing the expensive bottled water prices at the Long Island venue.

Many of the 2011 performers have been on the tour more than once, including The Devil Wears Prada, Attack Attack!, Big D and the Kids Table, Every Avenue, Less Than Jake, Relient K and Unwritten Law.

In the traveling festival's 17-year history, the Warped Tour has never been defined by one genre. Performers have been classic punk (NOFX, Bad Religion), emo-punk (My Chemical Romance, Fall Out Boy), pop-punk (All Time Low, We The Kings), and even rap (Eminem).

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Lyman continues to push boundaries on the "punk rock summer camp," this year booking reggae (Pepper), bluegrass (Larry And His Flask) and alt-country (Lucero) artists.

"I think he's trying to expand and diversify a little bit," said Lucero frontman Ben Nichols of Lyman's decision to book his band. "And we're definitely on the diverse side. We'll see if it works. I'm curious to see if Warped Tour can become something bigger than it already is and something more inclusive than it already is. With guys like the Bad Rabbits and us out here, he's definitely taking it in a new direction."

Also diversifying the bill was the Bad Rabbits, who were both a crowd and crew favorite. The backstage and sidestage area was packed with dozens of workers and other band members -- a crowd that the band's tour manager said has only been growing each day. The audience grew, crowding the small Skullcandy stage as the band broke into dance numbers and joked with fans, proving that they are just as good of showmen as they are performers.

Video: Bad Rabbits' "Girl I'm Like Damn," Uniondale, N.Y., July 23

Fans flocked to the mainstage for Gym Class Heroes' early evening set, where the band played vocalist Travie McCoy's solo hit "Billionaire" in addition to Gym Class tracks including "Cupid's Chokehold," the band's new single "Stereo Hearts" (feat. Adam Levine) and "Peace Sign/Index Down," for which the entire audience threw their middle fingers in the air. "Billionaire" started out with a track of Bruno Mars' vocals, but the crowd was singing so loud that McCoy turned off the track and had the audience sing instead.

GCH hasn't been on Warped Tour since 2008, and this is the first tour since the band took a break, allowing McCoy to record his solo debut and the other members to work on their own side projects.

"Being back on Warped has been phenomenal," said bassist Eric Roberts. "We're working out the kinks technically, but as far as the reception from all the kids, it's been so inspiring. To go to all these signings and have kids be like, 'Oh my gosh we missed you so much.' It just makes me want to work that much harder to get our album out and put on great shows."

Video: Gym Class Heroes Perform Travie McCoy's "Billionaire," Uniondale, N.Y., July 23

The audience and stage were both packed for 3OH!3's set, as frontmen Sean Foreman and Nathaniel Motte burst on stage, running from side to side and jumping around, flying through their electro-pop hits "My First Kiss," "Don't Trust Me" and "I'm Not Your Boyfriend Baby." The Colorado duo joked with the crowd, calling out to "Justin Bieber" and "Jesus Christ" in the audience and pulling a boy in a banana costume onstage to dance.

The day closed with mainstage sets by hardcore bands The Devil Wears Prada and A Day To Remember, and kids piled into cars and shuttle buses, just grateful for the air conditioning.