There are so many rock songs about highways that you could spend years trying to listen to them all, but this edition of Clash of the Titans narrows our focus down to two of the greatest: Deep Purple's 'Highway Star' and Judas Priest's 'Heading Out to the Highway.'

Deep Purple's 'Highway' rolled first, arriving in 1972 as part of the band's hit 'Machine Head' LP. Written on the road, initially as part of the band's semi-tongue-in-cheek response to a reporter asking about the band's songwriting technique, it kicked off the album in perfect Purple style, jamming a Jon Lord organ solo and a Ritchie Blackmore guitar solo into its six-minute running time. Too long to enjoy the level of pop radio dominance enjoyed by the big 'Machine Head' hit 'Smoke on the Water,' 'Highway Star' has nevertheless established itself as a staple of the band's live sets, appearing on multiple concert recordings along the way.

'Heading Out to the Highway' appeared a little less than a decade later, surfacing on Judas Priest's 'Point of Entry' album in 1981. Flush with record company cash after the success of the previous year's 'British Steel' LP, the band decamped to the sunny island of Ibiza, off the eastern coast of Spain, to work on 'Entry,' and emerged with a rowdy 10-song set that offered a rawer and more spontaneous version of Priest's emerging sound. While not as popular as 'Steel' or the following year's massive 'Screaming for Vengeance' album, 'Point of Entry' spun off several hits -- including 'Heading Out to the Highway,' which broke the Top 10 on Billboard's rock chart.

So which 'Highway' would you rather ride? Check them both out below, and remember: you can cast a ballot once an hour between now and when voting ends on Sunday, Oct. 19, at 11:59PM ET.

Listen to Deep Purple's 'Highway Star'

Listen to Judas Priest's 'Heading Out to the Highway'

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