Gates are open for day one of the Austin City Limits Festival.

A sizable crowd had already amassed as the "Star Wars" theme song blared over the loudspeakers at 11 a.m. on Friday. The folks who were smart enough to pack all necessities into their pockets made it onto the festival grounds fastest, charging through the bag-free line and hustling to stake out spots for their favorite acts.  We suspect a few fest-goers of somewhat advanced age with chairs on their backs planned to pick the best possible vantage point for Paul McCartney's headline set later tonight. (A lot of the artists playing ACL this year are also excited about Sir Paul's set)

RELATED: Going to ACL Fest? Here's what you can take

ACL Fest is sold out today, so we expect lines will get longer as the day progresses. Festival staff warns that peak entry times are between 3 and 5 p.m., so if you must arrive sometime in that window, be prepared to wait. Also be prepared for an airport style security check at the gate and hot temperatures this afternoon. All liquids have been banned from ACL Fest this year, so leave your factory-sealed water bottles at home, but do bring a refillable water bottle. There are plenty of filling stations throughout the park and staying hydrated is essential.

Check out our hourly recommendations for can't miss acts and have fun at the fest!