Van Halen's "Beautiful Girls" faces off against Bryan Adams' "Summer of '69" in the first round of our Greatest Summer Song battle – and your votes determine the winner.

We've selected 32 of classic rock's best summertime songs, and paired them off in 16 first-round duels. Over the next five weeks the field will be repeatedly cut in half by your votes, until we arrive at the greatest summer song of all time.

There's plenty of Van Halen songs that could have made this list. In fact, one from the band's Sammy Hagar-fronted era, "Summer Nights," is featured in another battle. But the "toes in the sand" line from Van Halen II's "Beautiful Girls" made it our choice from the David Lee Roth years, over their covers of "Ice Cream Man" and "Dancing in the Street," among others.

When it came to Bryan Adams, our choice was much easier. "Summer of '69," from the Canadian rocker's 1984 multi-platinum album Reckless, is a wistful, nostalgic look back at the carefree days of his youth – complete with drive-in dates, heartbreaks and his first guitar.

You can vote once per hour in each of the 16 first-round battles until voting closes on July 27 at 11:59 PM ET. Your choice for the Greatest Summer Song of all time will be revealed on Aug. 25, 2015.

Listen to Van Halen Perform 'Beautiful Girls'

Watch Bryan Adams Perform 'Summer of '69'

 The Top 100 Albums of the '80s