Kennywood, a nearly 130-year-old amusement park outside Pittsburgh, Pennsylvania, is tightening its summer chaperone policy as parks around the country experience violent brawls and unruly teen crowds heading into the heart of the season.

The popular Pennsylvania amusement venue said guests ages 15 and under must be accompanied by a parent, guardian or other supervising adult during all operating hours, effective June 12. The updated policy will apply through Sept. 7, according to a company statement.

The move follows several high-profile incidents at amusement parks in recent weeks, including at Six Flags St. Louis on opening day, when multiple brawls involving as many as 100 people prompted a police response and forced the park to close early. 

Kennywood’s news also follows an opening-day brawl at Hersheypark in Pennsylvania, in which 55 people — including 52 minors and three young adults between ages 12 and 19 — were charged after a large fight broke out on April 3, according to police.

“This was a proactive measure and part of our ongoing commitment to preserving the welcoming, family-friendly atmosphere that has defined Kennywood for nearly 130 years,” a company spokesperson told Fox News Digital.

In a recent Facebook post, Kennywood wrote, “We are aware of social media posts circulating regarding a possible unauthorized gathering at the park. We have zero tolerance for disruptive behavior.”

Kennywood said its updated policy is intended to “enlist the cooperation of parents and other adults responsible for children” and help the park provide a safe and enjoyable experience for guests. 

The park also noted that responsibility for children attending Kennywood rests with parents, guardians or assigned chaperones — not park personnel.

Under the new rules, guests who cannot show proof they are at least 16 will not be allowed to enter without a qualifying chaperone. The chaperones must be at least 21 years old and present a valid government-issued photo ID. 

Each chaperone may accompany up to six guests ages 15 and under.

When the group enters the park, the chaperone must be present — and the chaperone must remain inside the park for the entire visit, though Kennywood said the adult does not need to physically stay with the minors at all times.

Guests 15 and under must be able to contact their onsite chaperone throughout the visit.

The park said the new policy extends its previous summer chaperone rules from a 4 p.m. start time to all-day enforcement, while lowering the age requirement from guests 17 and under to guests 15 and under.

Recently, so-called “teen takeovers” have disrupted parks, beaches, malls and other public spaces in several cities. Authorities have said some gatherings, often organized or fueled by social media postings, have escalated into fights, arrests and emergency crowd-control responses, as Fox News Digital previously reported. 

Hersheypark later implemented photo reentry verification after fights between teens disrupted its opening weekend, according to Fox 43.

The park said at the time that safety was its top priority and that guests who violated its policies would no longer be welcome.

Kennywood said its updated chaperone policy will be enforced at the entrance and throughout the park by management and security. Any guest 15 or younger found inside the park without a qualifying chaperone could face removal. 

Organized and ticketed group events — including school, church, corporate, summer camp and sports group outings — are exempt because they already have existing chaperone policies and practices, according to the park.

Online, many people praised the owners for taking decisive action.

“Good on them for getting ahead of any potential issues,” one Reddit user wrote. 

“This is not normal kid behavior anymore that’s being cracked down on,” another person said. “This stuff has become way too common.”

“Love this idea,” a third person said. “Just wish they’d bring back a non-rider entry fee or other discounted pass for chaperones who don’t plan to ride.”

Kennywood is located in West Mifflin, about 10 miles southeast of Pittsburgh. 

Opened in 1898, it is one of only two amusement parks in the U.S. designated as a National Historic Landmark. (The other is Rye Playland in Rye, New York.) 

The park said all guests must also pass through a weapons detection system at the front gate during the summer, and only bags 15 inches by 15 inches by 15 inches are permitted — with exceptions for medical and diaper bags.

The western Pennsylvania staple has been known for generations for its classic rides, including the Jack Rabbit roller coaster, as well as its popular Potato Patch fries.