You haven’t lived until you’ve heard Polish death metal band Decapitated in a sauna at sunrise. Or been serenaded with satanic death growls while eating French toast, pasta Alfredo and tiramisu, respectively. I’ve been whipped in the face by humid purple hair at a beach bar named Margaritaville and witnessed 10-second rainstorms and double rainbows. I have smelt far too much sweaty leather. I have been officially indoctrinated into the cult of 70000 Tons of Metal.

“You’ll need a vacation after this vacation” reads a Royal Caribbean brochure for the annual four-day tour sailing from Miami to the Caribbean: a swanky cruise that’s part MTV Spring Break with a smattering of satanists thrown in for good measure. Its success has inspired multiple metal cruises to launch around the world, but an entire liner hosting 60 bands and 3,000 metalheads from 80 countries makes 70K the daddy of the scene – in both scale and infamy. At the inaugural 70K in 2011, revellers drank the cruise dry in less than 24 hours, selling more alcohol than in the entirety of Royal Caribbean’s cruises (70Ks surprising partner) for the year combined.

There’s something extremely metal about being trapped on an upscale cruise ship filled with endless shrieking, like banqueting in hell – where the feast is eternal, but impossible to eat. Extreme metal plays on a loop around the ship during the festival: in the casino, the opulent three-tiered dining hall, the shopping village, the art gallery, the spa, and the parlour serving free pizzas until sunrise. Instead of Robbie Williams and Madonna, the karaoke machine has been reprogrammed with Lamb of God and Slayer.

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Metalheads thrive on this level of campness. Subversion is a love language for us – a process of feeling seen. So, we wait patiently for a morning set by Norwegian folk metal band Trollfest on our small, floating asylum. The sun is blistering, but the fans are committed in their black attire, with some even wearing fur, like Vikings.

The band begins, and when the sea wind whips their long hair, it looks as if it’s being blown back by the force of their own sound. All day, the music is eye-wateringly loud, suffusing the entire ship and all the bodies within in a vibrating haze. Shows go on until 6am. At almost any given moment, a crowdsurfer is in the air, averaging around six per minute and 360 bodies per hour.

There is no sleep to be found on this barge to hell (incidentally, the name of another metal cruise). Instead, I snatch several naps throughout the day designed around bands I’ve circled on a setlist: Mork, Pessimist, Suffocation, Hate. At each alarm, I roll out of bed, don my black Crocs (the event’s unofficial “It” shoe) and shuffle out the cabin. There are four stages around the ship, and I can reach each of them within 30 seconds to three minutes. There’s something spectacular about wandering into an Onslaught show at 2am, threading through a mosh pit half-awake. As we start to shove each other around, I sense I may be nearing peak joy.

I’m not big on medieval metal, but get roped into seeing Swedish power metal band Twilight Force while riding an escalator. The band is a kind of Lord of the Rings pantomime act with a hobbit and elf shredding on guitars, and it is here, a mere hour after watching Bristolian thrash metal band Onslaught that I have a life-affirming musical experience. In the circle pit – a standard mosh pit variation where the crowd forms a big hole to stomp in – we all link arms and start to jump in a ring in unison, giggling like a playground of preschoolers.

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As I leave, I pass the karaoke bar and see an old, bearded man singing Whitney Houston’s The Greatest Love of All in a hellish death metal growl. The effect is strangely serene. Its sound follows me out through the casino, as I survey the bars below, which are all heaving.

Showering the next morning, it dawns on me that the karaoke balladeer was probably a famous musician. His death growl – the unclean vocals signature to the genre – were not those of a mere amateur. And a large draw to 70K, for many fans, is the opportunity to share space with the artists they love. Meet-and-greets, music clinics, acoustic sets and even shore excursions – think snorkelling and swimming with dolphins – form part of the package.

With metalheads so dispersed across the ship, it’s easy to forget the sheer scale of the operation – but on the final night, it seems like the entire ship has congregated on the open-air pool deck to watch Sepultura’s 40th-anniversary show. From the first riff, everyone starts to jump. The weight is so intense that the ship sinks on every beat, the buoyancy of the water creating the effect of a trampoline.

The sheer whimsy of being alive in the middle of this hot, moonlit ocean is overwhelming. I look around for mirrored recognition from my peers and see a man I know. This muscly, tattooed, Tarzan-haired circle-pit frequenter, perennially shirtless, is right next to me, and I understand the look on his face. It’s one of pure shock and delight, that becomes more acute with each leap that he takes, as if he’s springing into a ferocious new realm characterised by noise, chaos and pure anarchy. I smile, raise my fist and start to bounce.

The 2025 edition of 70000 Tons of Metal was priced from $1,689.70 (£1,304); tickets for the 2026 season will be announced soon on 70000tons.com.

Where to stay in Miami

With 70K pre-parties held in Miami (post-cruise parties are held in Hollywood Beach), Citizen M Miami Worldcenter’s downtown location is unbeatably close to most nightlife, and a 30-minute walk to PortMiami.

Recover from the 70K’s excesses at Eden Roc Miami Beach Resort. It is home to three large swimming pools, a spa to rest weary bones, and even a hair salon should your mullet need some maintenance.

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