Organizers delayed opening the gates to the concert area by more than two hours Sunday while laying hay, gravel and bark mulch to contain the damage. The former Loring Air Force base received heavy rain in the days preceding the “It” festival.

“We’re as frustrated as the fans are,” said Adam Lewis, spokesman for Great Northeast Productions, which put on the rock band’s festival.

Lt. Darrell Ouellette of the Maine State Police reported six arrests for assault, none involving weapons, and about 20 drug-related arrests by Sunday afternoon. But authorities were pleased overall with how the jam band’s fans conducted themselves in a confined area.

At around 2 a.m. Sunday, the band performed its fourth set of the night on top of Loring’s air traffic control tower.

Phish played an extended jam amid billows of red and blue smoke, witnesses said. Lights illuminated three aerial gymnasts wearing rapelling gear who bounced off the tower’s sides.

Many fans who stayed up the entire previous night while stuck in traffic fell asleep before the unannounced performance. Brian O’Neal, 28, of Nashua, N.H., missed the early-morning show but didn’t seem to mind, as he praised the festival’s creative vibes.

“You always have this carnival-like atmosphere,” O’Neal said. “It’s like a city in here … a city for Phish fans to live in their own little world.”

That makeshift city, the largest in Maine this weekend, included miles of cars, trucks and RVs parked along Loring’s runway. Fans sold everything from cigarettes and absinthe to vegan-friendly french fries from the back of their vehicles.

The event even had its own 100,000-watt radio station. Phish bought air time from 3 a.m. Friday to 2 a.m. Monday on WQHR, 96.1 FM. The station, which can be heard for 100 miles in every direction, was renamed The Bunny.

It aired Phish’s concert sets live and filled the rest of the day with others bands’ music and roving reports from the concert grounds.

Gary Turismo, a disc jockey in New York City who spent time living in Burlington, Vt., where Phish are based, joked that The Bunny is challenging Clear Channel, which owns more than 1,000 stations nationwide.

Turismo was waiting at the finish line of a 5K race Sunday that included roughly 1,500 runners. The 100th Running of the First Annual Runaway Jim Memorial 5K took its name from a Phish song.

Although fans traveled to northern Maine from all across the country and seven foreign countries, the race’s winner came from right down the road. Justin Easter’s time was almost a full minute faster than Phish guitarist Trey Anastasio’s prediction of 16 minutes.

Easter, 22, of Presque Isle, is a former runner for Bates College who now cross-country skis professionally. He’d heard a rumor – false, it turned out – that entrants would have to run naked.

“If it was all naked, yeah, I would have done it,” he told reporters.

Other festivalgoers began their Sundays at a more leisurely pace, chatting, playing guitar or smoking a joint along Loring’s runway.

“You just wouldn’t see this community anywhere else,” said Katie Boitz, 21, of Laconia, N.H.