For those old enough to remember when MTV Europe still played music back in the 90s, performances shot at Roskilde were an essential part of the station’s alternative output, and rock fans looked upon the festival in Denmark - land of Hamlet, Lego, Hans Christian Andersen and remarkably tall people - as one of the must-do European events of summer.

So what happened? In 2000 there was a tragic accident where nine people died during a Pearl Jam set, then MTV began screening The Osbournes and soon eschewed its musical output for reality TV. For whatever reason, the festival dropped off the radar, in the UK at least.

That’s not to say the crowds or the line-ups have diminished in any way during the last 13 years: last year Roskilde Municipality hosted Bjork, Bruce Springsteen and The Cure and this year they managed to clinch Metallica’s only European show of 2013 and attract arguably the world’s most talked about pop star, Rihanna.

For all the coverage Glastonbury gets, Roskilde is just one year younger (and has taken no breaks like its contemporary) and is regarded as an essential stop-off point for the world’s biggest musical acts. There’s also - like Glasto - a fascinating art scene that’s grown up within the festival (though I shall be exploring that in a forthcoming piece). With all of this in mind we thought it time to check it out for ourselves, so here are some things we learned at Roskilde Festival.

Most bands get one hour at Roskilde - Metallica get as long as they like

Legend has it that Cerebral Ballzy - the awesome smash and grab hardcore punk band with a set consisting of one minute face punchers - were forced to return to the stage at Roskilde to eek out their hour or face the prospect of not being paid last year. It's a noble and egalitarian ethos allowing all bands - no matter how big or small - to get an hour no matter what, though a group like Parquet Courts will only suffer under these conditions. Also a bunch of one minute wonders, they throw in a couple of improvisational dirges to make the time pass and watch the crowd dwindle before their very eyes.

More professional and established artists on the Orange Stage (that Orange has nothing to do with the French phone company by the way - it's just orange) get to play for longer. Country legend Kris Kristofferson brings his Scandi name and the Texan sun to the main arena for more than an hour and a half - just the Rubber Duck, a guitar and a voice that more or less holds up for a man who's seen the best side of 70.

And then there's Metallica, the band they couldn't kill. They keep coming back like revenants. Eight encores in and they morph back onto the stage like the T2 in the Terminator movies. They're a turd that won't flush. They don't go on for as long as Springsteen, thank God (does he give the fans what they want or does he just thrive on unquestioning adulation like the insecure deity?) but it feels excessive nonetheless if you’re not completely insane.

Though given that it's a homecoming gig for Lars - and they manage to squeeze in the (possibly not intentionally) hilarious ‘Carpe Diem Baby’ - then we'll forgive them. 2013 is meant to be Metallica's year off, but this one-off European date is proof they've not been slacking. As per, every cymbal splash and peripatetic fret impression is in its rightful place, and James Hetfield is his usual smarm ball/charm ball self. Quite good, all told, but that’s a serious amount of noise for a band that wanted a rest. Speaking of which...

Even Savages get tired

"I am here," sings Jehnny Beth, and if it’s a festival in 2013 then that’s probably true. Savages were recently announced as main support for Queens Of The Stone Age in the U.S. and are already pencilled in for more than forty dates this year across the world on various bills. Last month I saw them tear La Maroquinerie in Paris a new arsehole, and they'd just flown in from the U.S. that afternoon having appeared on Late Night With Jimmy Fallon the previous evening. Glastonbury, Bestival, Rock en Seine, Kuudes, Gorky Park... the schedule is unremitting and definitely unforgiving. It’s no wonder then that sometimes Savages get tired. In fact it’s during ‘I Am Here’ - a song not overly abundant with loquaciousness - that Jehn has to stop the music due to a brain cloud. “It happens, you know," she tells the crowd defiantly. "It just happened right now. I'm tired." They turn it around with a magnificent ‘Flying To Berlin’, and one wonders if these days they spend more time in the air than they do on the ground.

Matthew E White's band is stylish, and then some

Who knew the ‘E’ in Matthew White's name stood for elegance of the sartorial kind? Is that a cyan headband the drummer's wearing and will you just take a long, envious look at the bass player's tight, crocheted vest? Even Nicholas and Claus - the stiff, hired Nordic brass section - manage to look cool by association. Matthew E. White has flowing locks and golf pants, while his cohorts look like long lost acid children who’ve finally been found again rooting through a kaleidoscopic vintage shop. And hey Mr. Bass Man, I hope you walked through the airport looking like that: sunglasses, flat cap, beard, flairs and tight, striped muscle vest, like Donald 'Duck' Dunn on rollerskates. The music has a suitably 70s vibe too and for an hour we're displaced and nostalgic for a time that never was.

Hip hop stripped of its machismo is a beautiful thing

Azealia Banks, in wasp sunglasses and skintight brown and orange bikini, also looks majestic when she finally bothers to show up. Yung Rapunxel’s show is really gay, and all the more beautiful for it. Her DJ Cosmo, is camper than a Liberace box set at Christmas, and that’s before her Lycra-clad male dancers have entered the fray. Banks throws herself into the choreography as pink and neon blue palm trees appear on the backdrop interspersed with dolphins, zebras and illuminati eyes. We’ve not been holding our breath for the album, but the robust and unremitting ‘No Problems’, apparently lifted from the forthcoming debut release suggests that maybe we should.

Mykki Blanco appears on stage in a pair of nipple tassels, and like Azealia, she has remarkable onstage presence. “Who wanna rumble with a beast like Betty?” asks Mykki, and you’d have to say “not me”, because it’s taken some serious gusto and some even more seriously precocious talent to make queer hip hop as prevalent as it is now in such a short space of time. Hip hop had looked like it would stagnate forever, but for brave, pioneering artists like Blanko and Banks who couldn’t give a shit what others think of them; they deserve all the adulation they get.

Guitar soloing is creeping back in

Since punk swept through music like a new broom, overindulgent guitar twattery in the mainstream had remained largely in the past in the form of clips from The Old Grey Whistle Test. It was as though brains became hardwired to hate interminable fret-wankery of any kind - and if you didn’t like it you’d have to join a fucking jazz band. Twiddling between bars where there are no vocals has thankfully been confined merely to jam sessions in backwater boozers in parochial towns, but is it going to stay there? Josh Homme was way more noodly with his six string that we’ve ever noticed before (though we forgive him just because he’s hired a Bryan Ferry lookalike to tour with Queens Of The Stone Age). Likewise, in another alarming development, Ruban Nielson of Unknown Mortal Orchestra couldn’t keep his fingers from crawling all over his own neck. Even comedy chipmunk and career northerner Jake Bugg was getting fidgety with the digits. Belligerent soloing is on the way back by the looks of it. Be warned.

Kendrick Lamar provides the scheduling nightmare

Here are two rules to remember in life: 1. Don’t walk around a festival with a 30-foot Pantera flag, because you’ll have to carry it around with you for the whole duration if you don’t want it nicked. This means you’ll look like a dickwad when you’re holding it and watching Rihanna. 2. Don’t put Kendrick Lamar in a tent. Thousands upon thousands of people will surround that tent sobbing that they can’t get in if you do.

At every festival there’s a scheduling nightmare and the Kendrick Lamar debacle was Roskilde's this year, which was twice as annoying given that the main stage was vacant but for - one presumes - roadies setting up oil drums for the clown to bangalang in Slipknot. And what a tired and washed up spectacle they’ve become.

You can set your clock by Kraftwerk

Having been all set to see Azealia Banks twice in the past only for her to blow the shows out, her turning up 45 minutes late is something of a relief, especially given that we had to bail on Angel Haze when she took more than an hour to arrive the previous night. Rihanna also got the hackles of some of the crowd up doing an Axl and turning up half an hour late. Kraftwerk, conversely, arrived dead on 10.00 p.m. and forced us to scamper through panes of glass, watermelons and chickens in order to arrive before the conclusion of ‘The Robots’, which sounds fresher than we’ve ever heard it with the subwoofer of the main stage pumping hard. We might have known that Kraftwerk would be the band to arrive on time, though if you’re expecting rhetoric about German efficiency then you’ll have to wait until they hand out 3D glasses that actually work.