Thousands braved heat, humidity, mud and the threat of stormy weather yesterday to attend the first festival in three decades at Diamond Head Crater.

Most in attendance had read or heard the list of rules that everyone allowed inside was bound to follow — no backpacks, no cameras, no umbrellas, no homemade food.

Many, such as Marine veteran Eddie Knoebel, remembered how things operated for crater concerts in the 1970s.

"Back then, there were no rules, really," said Knoebel, 49. "You could smoke anything, pop any pill. ..."

Show emcee Ken "Hutch" Hutchinson of Oldies 107.9 also remembered the crater concerts of old. "It was a bunch of hippies in here smoking pot, basically," said Hutchinson, recalling how past shows had no seating, so "when it would rain, we'd sit in the mud."

This time around, after weeks of rain, the crater was hot, sunny and humid two hours before the concert was set to begin. By showtime, skies had grown overcast. Some were saying a storm was on the way.

When the show hadn't started by 2:20 p.m., Hutchinson assured the crowd that the action would get under way soon. But confusion, caused in part by the unprecedented torrential rains the day before, held things up for about 40 minutes.

"The rains Friday messed us up big time," said Armando Morales, production manager for WAR.

"All these sound checks we were doing earlier, that was supposed to be done yesterday. We're more than 24 hours behind today."

Donnie Becker, who flew in from Maui for the show, said that if there were people who worried about getting rained on, they simply hadn't bothered to come.

"And the people who did show up don't care if it rains," said Becker, 48, who attended the last crater concert 30 years ago.

"Look, everyone's got a smile on their face. This is like aloha — this isn't like a show at some stadium. This is a very special, sacred place.

"I think so many people were waiting for this to happen."

Milo Rhyne, 54, was among the waiting. He echoed Becker and others who insisted that they had come to be entertained.

"Rain? Nah. It's not going to happen," Rhyne said.

"And even if it does, we'll stick it out."

Although the crowd skewed toward baby boomers, the fan mix came in all ages.

University of Hawai'i students Adam Lowrie, 24, and Kelly Nausid, 22, said they were there mainly to see the Steve Miller Band.

"But I heard WAR is really good, too," Nausid said, "because my parents went to see WAR when they were our age, and they thought they were fabulous."

Crews had worked overtime to set up hundreds of wooden pallets for chairs in front of the stage and for walkways around the dozens of food, crafts and T-shirt booths.

But there was plenty of mud left over from Friday's downpour for those who ventured off the pallet and onto the grass.

Fans three-abreast stretched in a long line that snaked its way to the booth selling T-shirts commemorating Diamond Head Crater Celebration 2006. But the busiest and most popular attraction — apart from the headliner stage performances — was the beer booth, as evidenced by the throng crowded around it all afternoon and evening.

Bartender Jeff Renner said he and his crew were prepared to go through 260 kegs —and even more if necessary.

"We can handle the demand, whatever it is," he said.

Meanwhile, registered nurse Francine Dudoit was one of about a dozen volunteer nurses and nurse practitioners with the Waikiki Health Center who were standing by in case anybody got sick or hurt.

"We're ready for anything," Dudoit said about halfway through the event. "So far the only trauma we've had is an usher who cut his leg on a pallet.

"But everybody's getting pretty lit.

"And the night's not over."

Reach Will Hoover at whoover@honoluluadvertiser.com.