The free shuttle is at Republic Square! There is no parking at Zilker Park for the ACL Festival, so take the free shuttle instead - a short hop to the park! Board at Republic Square at the corner of 4th and Guadalupe streets, and you'll be dropped off at the Festival entrance on Barton Springs Road. When you're finished rocking, hop back on for a return trip. The shuttles begin at Republic Square at 10 am and make their final return from the park at 11 pm, Friday-Sunday.