Anyone under 18 will need an adult chaperone to attend this year's Contra Costa County Fair.
The new rule is in response to a series of fights that broke out at last year's fair involving groups of minors.
"It's not just last year, it's every year," said Richard Bell, an Antioch resident who attended the fair's opening day on Thursday. "Kids don't know how to act. Everyone wants to act grown and beat up people from school."
Bell and other fair attendees interviewed Thursday are in favor of the new rule.
"I think it's a pretty good idea," Antioch resident Joann Doan said. "I know they had a little bit of problems last year, so I think it's good to have more supervision."
The Contra Costa County Fair is only a four-day event, but organizers said the new policy is intended to keep people safer through its duration.
Fair officials said the new policy also places a limit on the number of minors each adult, who has to be at least 25 year old, can bring in.
"For each chaperone, they can only have four youth, 18 years or younger with them," Contra Costa County Fair CEO Joe Brengle said.
The Contra Costa County Fair is not the only site that has adopted a similar policy after brawls on its grounds.
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Last year, Great America in Santa Clara adopted a similar policy requiring minors to have a chaperone who is at least 21 years old.
