By Sarah Jane Griffiths
Newsbeat entertainment reporter
It was fireworks and flames from one of the biggest metal bands in the world, as Metallica brought day one at Leeds Festival - "Rock Day" - to a close.
Fans responded well to the elaborate stage set-up.
Twenty-two-year-old Richard Sewell said: "Amazing, that's the sixth time I've seen them now. Probably the best too. I love it when they have all the fireworks."
Tyler Logan, 17, is also a flame man: "It warmed us right up - it was a bit cold and when all the flames came up it was like…ooh, heat!"
After a spectacular finale of Enter Sandman, most of the huge crowd had started trickling off before the surprise encore of So What.
For some fans it was a long time coming. New Zealander David Malpass travelled up from London: "I've been waiting all my life to see them and they came through.
"Everything that I wanted - possibly a little bit more. My favourite bit? Nothing Else Matters, or Sad But True, it was all just awesome.
"I've been waiting since I was about 12, now I'm at least twice that, and here they are finally. Metallica. Me. Leeds. Awesome!"
Fans also got a taste of a new song, Cyanide. It's on their forthcoming album Death Magnetic which is scheduled for release next month.
Metallica played Cyanide - a new song from their upcoming album
Unfortunately some weren't so keen on Metallica's performance, like Kirsten Keats, who seemed to have been dragged there.
She said: "I was kind of bored, sorry! I thought I knew more than I did. I probably should have gone to watch The Kills, that would have done it for me.
"It's one of these bands you think you should see in your lifetime and now I have I'm not that fussed."
But there was plenty more on offer for non metal-heads.
Pendulum had the Radio 1 tent exploding with the longest version of Slam that they could manage. Digitalism and The Cribs were other stand out favourites.
Slipknot pull out
Feeder got moved up the running order on the main stage after Slipknot drummer Joey Jordison's broken ankle saw them pull out.
Frontman Grant Nicholas chatted to Newsbeat just before their set, and confessed he was a little bit concerned about flying bottles that might be aimed in their direction.
Feeder were a bit anxious about filling in for Slipknot
Nicholas said: "I'm actually a little bit nervous because it's rock day and I'm just wondering how we'll do with some of the heavier Slipknot fans who are upset they're not here!
"But we do kind of crossover, and I have seen kids at Feeder gigs wearing Slipknot T-shirts."
The band also said they weren't ashamed of pumping out a greatest hits set.
"We haven't toured the album yet, so we feel it's a bit too soon to be playing the new stuff. This festival we'll play something from all our records.
"If it's too poppy, well, at a festival you need to hear a song you know."
They didn't disappoint either - with classic sing-a-longs provided courtesy of Just the Way I'm Feeling, Feeling a Moment and Just a Day (yes, they really are all titles of different songs).
Next up on the main stage though, it was time to prove rock can be fun too, with Tenacious D.
Jack Black chose a wizard outfit to start their set, while bandmate Kyle Gass didn't disappoint in a bright green dinosaur outfit that wouldn't be out of place at a kids' party.
Tenacious D (pictured last month) wore odd costumes for their set
The "rock panto" theme continued when a huge robot joined them on stage to help their dance routine, soon to be replaced by Satan for their "rock off".
Plenty of noise was made for Master Exploder, before a very sweaty Jack brought out his sax-a-boom: a plastic toy saxaphone.
One of the biggest sing-a-longs and cheers came with "one for the ladies…", the ever-so-slightly unprintable song F*** her Gently.
The crowd seemed to know all the words too, saving their loudest voices for the rudest.
Tribute also proved a crowd-pleaser and the band admitted Leeds was the biggest crowd they'd ever played to.
The Arctic Monkeys spent the afternoon enjoying a beer or two in the guest bar, before frontman Alex Turner made his first official festival performance with side project The Last Shadow Puppets.
They took a 16-piece orchestra onto the Radio 1/NME stage with them - to one of the largest crowds of the day.
Singles The Age Of The Understatement and Standing Next To Me were the big crowd pleasers.
But dressed in mod suits with moody lighting, Alex and Miles Kane, who also performed with his band The Rascals, had the crowd hanging on their every note.
The guys seemed to be loving it too if the big grins on their faces were anything to go by and even thanked the crowd for being so great.