Late last month, Ibiza Spotlight published a short video recap of a closing party that wouldn't square with most people's idea of clubbing in Ibiza. The clip whisks the viewer through ceremony circles, past busy bars and up pitch-black paths. At one point, the camera hovers before a dazzling red arrow pointing to the right; in the background to the left, the frantic flash of purple lights suggests a rave in full swing. Moments later, you're in the middle of a lively dance floor, zig-zagging past couples making out, and looking up at a DJ, who seems to be playing in a tree. As the clip nears its conclusion, you travel up more dark passages, emerging into a smoke-filled amphitheatre teeming with hundreds of clubbers. The video has no sound, but you can still sense the noise and the energy.

The Zoo Project, which this year celebrated its tenth anniversary, is the closest event Ibiza has to a dance music festival. It says as such on its flyers, promising four open-air arenas, a swimming pool, massages, meditation and more at Gala Night, a sprawling, picturesque venue not far from the popular tourist town of San Antonio. Every Saturday between June and September, thousands of people flock to Zoo for a clubbing experience unlike any other on the island. It's colourful, relaxed and affordable, with a programme that features some of the best acts in underground house and techno.

Zoo's booking policy has earned it a strong reputation among promoters and music fans in Ibiza and further afield. Since joining in 2008, the party's chipper booker, Graeme Stewart, has made a point of bringing new acts to Ibiza and developing long-standing relationships with a deeper strain of artists who otherwise might not fit into the world of super clubs. The current residents roster includes Evan Baggs, Funk E, Tuccillo, Blackhall & Bookless and Samuel Deep—all great DJs with lots to offer but their sounds aren't suited to 2000-capacity rooms.

"It's gotta have a lot of groove to it, definitely," Stewart told me of Zoo's booking policy, on a hot afternoon at Gala Night. "It's outdoor, it's sunshine, it's people that are here on their holidays, and you've gotta be very aware and respectful of that fact. You can't just book someone who you think is gonna be almost deliberately obscure. People have spent a lot of money to be on this island for their one week off from what might be a mundane, boring, testing job. This is their week of sunshine and their week of escapism."

Ross Mogli, Lubka Pajerova, Adrian Browne, Graeme Stewart

On its flyers, the venue is referred to as "The Old Abandoned Zoo." This is a half-truth. Fantasiland, as it was originally known, was never a zoo in the traditional sense—no lions or tigers ever lived there. Built in 1975 by a company from Mallorca, it opened three years later as a family tourist attraction. There were parrots, monkeys, rabbits, sheep and seals. The venue's structure, including the seal pit, which today is Zoo's main club space, remains the same as when it was first built.

Fantasiland wasn't a profitable business, and in 1980 it closed. Until another company bought the venue in 1985, it lay abandoned—hence Zoo's tagline. The new owners saw its potential as an events space and reopened it as Gala Night, which is also the name of the restaurant/function room (and sometimes nightclub) situated to the south of the venue. (Among other things, it hosts a weekly dinner for local pensioners, featuring Ibiza's largest paella oven.) The animals were replaced with bands, a barbecue and a bucking bronco. Occasionally in the '90s and '00s, external promoters used the space, but nothing stuck. (In August 2002, MTV ran a one-day festival called MTV Aquasonic that featured 2manydjs, Audio Bullys and more than 30 other acts. It flopped, filling only half the venue, at a reported cost of €90,000.)

In August 2006, Adrian Browne and Lubka Pajerova, a pair of twentysomething promoters who'd had some success running boat parties in San Antonio, pitched a one-off event called Safari Party to Gala Night's owner, Bartolo Escandell. This was their third or fourth written proposal—the others had been rejected because they'd positioned the events as an afterparty for Circoloco and Cocoon. (For venue owners, that means hordes of wide-eyed ravers and unwanted attention from the police.) This time, though, Browne and Pajerova suggested a 4 or 5 PM start time. Escandell agreed, and the event went ahead on Saturday, September 6th, 2006, in collaboration with Franz Hager (AKA Defex) and Joe Burnley from The Minx Fx. In all but name, it was the first edition of Zoo.

These days, many people consider Gala Night to be the best venue in Ibiza. It might not match up to DC-10 or Amnesia for sound quality or raw, imposing power, but it makes up for this with a combination of natural beauty and a spacious layout. There are three dance floors—The Seal Pit, The Treehouse and The Living Room—plus a sunken arena known as Mandala Garden. A lush green forest encloses the venue, dappling its tan paths with sunlight.

It's a lovely space to explore, and you're always discovering new nooks and crannies. Nicki Kos, who oversees the themes for Zoo and also DJs as Milou, plays on this, bringing seemingly unremarkable parts of the venue to life. The décor is wacky, colourful and everywhere but it isn't overdone. The last time I visited, in June, someone had set up a game in which you thrash out beats using touch and real bananas. That same day, I did an interview in a cubby hole I never knew existed.

The Seal Pit and The Treehouse are the two main dance floors, hosting a mix of international guests and residents, while The Living Room is generally reserved for smaller label or party takeovers. The Seal Pit was there when Zoo started—the same amphitheatre where families sat in the '70s is now full of topless ravers jostling for space on the large red steps. The DJ booth is at ground level, separated from the crowd by a semi-circular pool and a small stage, where various dancers and acrobats in animalistic costumes take turns currying favour with the crowd. Sunset is the best time: in the gap between the amphitheatre and the booth you can watch the rich reds and yellows fade over the rolling Benimussa hills.

This is where the clubbier acts tend to play—DJs like Scuba, Will Saul or George FitzGerald, who play dance music with big moments. The combination of the smoke, noise and number of bodies means playing there can be daunting even for experienced artists. Stewart told me he's had to ply more than one big artist with shots to calm their nerves (he wouldn't say who).

One of Stewart's fondest memories of the space was when he booked Moodymann to play four hours in 2012. Kenny Dixon Jr. had played Ibiza once before, in the back room at Pacha in 2010, but the room was apparently empty. Sometime late in the afternoon, Stewart got an angry call from Dixon Jr., complaining that his pick-up hadn't arrived and his hotel didn't exist. It turned out he'd forgotten about his connecting flight to Ibiza, and was in Barcelona. He rushed to catch the original flight, missed it, and caught another that got him in around 10 PM, two hours into his slot.

"We gave DJ Sneak a ring," Stewart told me. "We'd been out with him the night before and he agreed, bless his heart, to stand in for him. We got him a couple of bottles of rum, and Sneak and Acid Mondays played back-to-back and got it underway for Moodymann to come in. The great thing was a lot of people had turned up expecting to see Moodymann and he wasn't there, but Sneak was, so they figured, 'OK, something had happened, no harm.' And then Sneak really had the place going and rocking and people by that point had almost, not forgotten exactly, but they really weren't expecting Kenny to come. So when he turned up, bandana on, only his eyes visible, his headphones already in, straight away bantering with Sneak... yeah, it was pretty amazing."

The deeper acts Stewart books, DJs like Evan Baggs, Molly and Binh, generally play The Treehouse, which in the last three years has grown into one of Ibiza's best-loved spaces. Back in 2006/7, it was little more than a trestle table with a pair of decks on it, but today artists play from a makeshift wooden treehouse, looking out over a long, wide dance floor that manages to feel both intimate and epic. Up above, dozens of coloured umbrellas hang suspended from army netting, glistening brighter shades in the sun. Groovy house works best during the day, while at night it can go one of several ways. I've seen Zenker Brothers rock it with techno, just as I've heard Margaret Dygas go dark and trippy, or Ron Trent keep it deep and soulful.

When I was there in June, Baggs totally owned the space. The New York DJ, who's been a resident since 2010, was meant to go back-to-back with Ben UFO but flight complications meant the Hessle Audio boss never made it. Baggs played for four hours, something that would be inconceivable elsewhere on the island. As he built from spacey, rolling house to ravier selections, his smile grew gradually wider. Every now and then he'd throw in a 2-step rhythm for extra swing. Just as the sun was setting, he played Joy O's "Ellipsis," the track's infectious piano stabs causing a scene on the smoky crimson floor. I couldn't tell who was having a better time, Baggs or the crowd.

"The DJs love the fact that people are dancing," said Stewart. "The amount of times they've said they've played at X club or Y club and there's people just stood chin-stroking, or stood in a mess in the corner. They love that people are just really having a fucking good time. It's quite unknown to a lot of people. And particularly because it's a big crowd but still quite intimate. There's a lot of people, but you don't feel as disconnected as maybe you do in some of the big clubs. You feel like they're really there dancing for you, having a good time because of what you're doing. And I think that makes a lot of people feel pretty special."

Part of what made Baggs's performance so electric was that until he turned up no one knew he was going to play. Zoo decided not to announce any of its lineups in advance in 2016, a move that's both unprecedented in Ibiza and contrary to the way the island's club scene works. With the exception of Circoloco, who announce their lineups weekly, most parties reveal a full season's bookings in one go, luring people into planning their holidays while flights are still cheap. For these promoters, their seasons are won and lost on the artists that will or won't play for them. Zoo, on the other hand, has slowly been able to back away from the messy politics of exclusivity deals.

"We'd spoken to a couple of people who are gonna play for us this year, who'd played for us in the past, really enjoyed it, loved it, said they wanted to come back, but there was just too much politics around it," said Stewart. "And we always avoid the politics of it, because it's boring and it's pointless, and it just gets people's backs up over nothing. People end up feuding over totally insignificant little things. So we talked about doing a couple of unannounced dates with a couple of guys. And then we just came to it—why don't we just do it all this way? We'll alleviate a lot of pressure."

It was a risk that paid off. Zoo pulled similar numbers to last year, while putting on killer performances that otherwise might not have been possible. Cocoon darling Ricardo Villalobos, for example, returned for the second year running in July, and there were standout performances from the likes of Scuba, George FitzGerald and B.Traits—all artists tied to multiple other parties. "All in all, as scary as it was, not leading with lineups served us really well," concluded Stewart over email. "Although they still play, it's not about the big names. The important thing is the music being played, and I think this really allowed us to push that."

Zoo could take this approach because the party doesn't rely on its bookings to pull crowds. This freedom is powerful. "I never want anything to be stale," Stewart said. "We do have a lot of repeat guests, but I'd never want it to get to a point where it's just fucking dull, predictable. We get a lot of people kind of on the breakthrough, but it's not done with a sense of, 'Oh we need to get these people now to prove that we're so far in front of everybody else.' It's generally because they're doing something new or something interesting, like Shanti Celeste. It was never done with the intention of 'She's gonna be massive, we should book her now and get her cheap and say that we've had her before anyone else.' We booked her because she's a really good DJ, putting out some really interesting music, and I love what she's been doing on NTS."

Celeste is one of an impressive number of acts to have made their Ibiza debuts at Zoo, joining the likes of Hunee, Jeremy Underground, Ron Trent, Margaret Dygas, Marquis Hawkes, Zenker Brothers, Soundstream, Dungeon Meat, Soul Clap and Seth Troxler, who played a Crosstown Rebels showcase at Zoo in 2009. Sometimes, as in Troxler's case, acts move onto bigger things, but that doesn't bother Stewart. People will come either way, so he just rolls onto the next act.

Stewart first heard about Zoo from its cofounder, Adrian Browne, at Back To Basics in Leeds, where Stewart's Riffraff night was hosting the back room. Browne was impressed by how many people Riffraff had brought down from Middlesbrough, where Stewart is from, so he asked him to programme alternate weeks at Zoo, which at that point had just opened. Things went well, and in 2008 Stewart joined full-time as a general manager, taking care of everything from the bookings to the ticket teams. Stewart admits the bookings weren't groundbreaking to begin with, mostly a mix of well-known locals and the occasional guest. He does, though, remember landing Johnny D "when no one could get hold of him," which helped put Zoo on the map.

Johnny D played in 2009, a summer that was pivotal in Zoo's ascent. At the tail-end of the 2008 season, DC-10 was shut down by the authorities. The club, home to popular Monday party Circoloco, didn't open again until October 6th, 2009, leaving a gap in the market. Though it was no longer open-air, Circoloco was still a daytime party playing a certain kind of music. Thousands of partygoers, used to weekly doses of [a:rpia:r], Dan Ghenacia and Tania Vulcano, suddenly had nowhere to go, and Zoo's audience expanded overnight. "Yeah, we started getting a lot of that crowd," said Stewart. "And yeah, it would be stupid to say that it didn't help us. But I think we would've got to where we are now anyway, but it certainly gave us a leg-up. It helped a lot."

One party that summer was particularly momentous. In the winter of 2008-2009, Luciano left Circoloco after two years as resident, just as he and his label, Cadenza, were at the height of their popularity. Luciano roamed the island in 2009, playing Cocoon, Monza and, on July 27th, Zoo, heading up a Cadenza showcase. 5,000 people turned up, by some distance Zoo's biggest-ever crowd. People were climbing the fences; some even bought scissors to cut through the wiring.

Until that point, Zoo was almost exclusively attended by British workers and tourists from San Antonio. Gala Night was less than a €10 cab ride away, plus the venue, which Luka Pajerova described as having "no regulations" back then, was already popular with that crowd because of Sh*t Party, an annual charity event for workers. Today, this demographic remains Zoo's lifeblood. Walk down San Antonio's infamous West End strip on a Saturday afternoon and you'll see dozens of Brits having their arms painted in the print of their favourite animals.

A sizeable chunk of the crowd at Zoo is unfamiliar with the artists playing. For them, Zoo is primarily about getting loose with their mates in a beautiful setting. In many ways, it's a purer relationship with music, not shackled by trends or tastes. Long-standing residents Blackhall & Bookless, who run the UK label and party Jaunt, told me over email that playing to a crowd like this "keeps you on your toes. We feel it always tests us, in a way. Because the crowd aren't as clued up with the sound we play, you have to keep them entertained and dancing. You have to be flexible. Also, most of the music they hear will be new to them, so it can be great for reactions."

Thousands of people responding with such force to a DJ they've never heard before can be inspiring, especially in a landscape like Ibiza, where DJs are placed on a pedestal like nowhere else. I asked Stewart how he felt about some of the crowd's general disinterest in the bookings, and he admitted it had taken him a while to come round to it.

"When we had Zenker Brothers last year, for their debut, there were a load of girls who were maybe on a hen party, and groups of guys on holiday—you know, the kind of things that to headsy people are dirty words, things that you wouldn't see in Panorama Bar, or on the floor at Concrete or wherever. But this place isn't either of those. We can still hold ourselves to the same really high musical standards, even if the crowds are never gonna be like they are elsewhere. And I think when I embraced that everything became brilliant. I was super happy. It's fucking joyous to see a Zenker Brothers or a Steffi or a Ryan Elliott, or whoever, playing and there's people who the day before may have been on a boat party or at Ushuaïa dancing to Avicii."

Zoo also attracts a crowd of knowledgeable house and techno fans. You can spot them easily—they're the ones not splattered with glitter and paint. A lot of these people gravitate towards the party after a season or two on the island, lured in by the unique bookings. Blackhall & Bookless said they've seen this unfold over the years. "The sort of clubber who 'thinks' they're in the know are put off by it. They'll tend to go to somewhere like Music On, as it's currently in fashion. But then the artists, clubbers and promoters who really know their music and follow their DJs speak very highly of Zoo, as they know the music policy is the most interesting on the island. They have the upmost respect for it."

This mix creates a carefree and unpretentious atmosphere. When I last visited Zoo, I got talking to a glamorous 47-year-old Dutch lawyer called Michelle, who had been coming to Zoo for seven years. She was with two friends, a married couple, who had stepped off the plane earlier that day. Michelle said that Zoo was her favourite party because it channelled the old Ibiza, when the core ideals were tolerance and freedom of expression. She thought the rest of the island had left those behind in exchange for VIP culture and clubbing on a grand scale.

Every year before the season starts, Zoo's entertainment director, Ross Mogli, and a couple of others hold a day of X-Factor-style auditions in The Seal Pit. At stake is a place in Zoo's 24-strong team of entertainers and performers, who, every Saturday, are tasked with embodying the party's loud, colourful spirit. There are giant pandas and ornately-feathered birds, semi-naked Tarzans and khaki-clad zookeepers. Most of the performers roam the venue, clambering over benches and pausing for selfies with punters. A smaller, more specialised team takes it in turns to perform short stints in The Seal Pit, where the energy on a good night can be almost gladiatorial. I saw two breakdancers in full gorilla suits battle it out in a whirlwind of hand glides and back flips, followed by two burly capoeira dancers from Brazil pulling off combos I haven't seen since my days playing Tekken.

Except for Elrow, no other party in Ibiza entertains its crowds so creatively. At most of the major clubs you'll find scantily-clad go-go dancers gyrating on a podium, which feels more voyeuristic than watching someone perform ballet or breakdance. That's not to say the performances at Zoo aren't sexualised, but they don't have the same seedy undertones. "Zoo is the only different thing you can find on the island," said Carmen, a dancer from Spain who's been with Zoo since 2014. "It's the only place where you can actually express yourself as an artist rather than just dancing on a box. At those parties, you're part of the decoration, it looks good, it goes with the music, it goes with the style, whereas here there's a connection that you have with the crowd."

One of the enduring moments from my recent visit took place in Mandala Garden, the arena dedicated to healing, massages and traditional Indian music. Everyone had congregated in the centre of the space, around a seven-piece band playing shuffling percussive music. There was a metal agago, a tabla, some shakers. It was late, and the young crowd were in a merry zone between sloshed and worn-out. Lads in tank tops and shades cut shapes; girls took selfies and hugged. It was a peaceful scene, a world away from the bustling dance floor a short walk away.

These contrasts are the magic of Zoo. It's an alternative, an enclave away from overcrowded clubs, stagnant bookings and divisions based on money or social standing. "You're not gonna get sandwiched against the wall, you're not gonna struggle to get to the bathroom, you're not gonna pay €15 for a beer that's gonna be warm in two seconds 'cause of how hot the club is," said Stewart. "You're not gonna have to deal with a lot of the things you have to deal with in the big clubs."

Towards the end of our conversation, I asked Stewart what Zoo's core principle was. He paused and looked away before answering. "Everybody's the same. It sounds a bit blasé and a bit 'house music' to say, but it totally is. There's no pretension here, there's no looking down on anybody—OK, this person doesn't know that DJ, but they're enjoying it all the same. That is the only core principle we've got. If you come and you're open to everybody else, and you're up for having a good time and listening to some good music—that's all we do here."