Kokomo Private Island: Fiji's private island resort reachable only by seaplane

The surf's so untapped round here that even the guide isn't sure where we should be sitting to wait for waves. So he throws a buoy over the side of our speedboat: that way we'll know if we're about to surf straight into coral. All across Fiji, thousands of Australian surfers are battling it out for waves; but here ... well, I wish just a couple of them were with me now for company. Because we're bobbing on the drop-off of a very deep-water passage on the edge of a submerged reef half-a-kilometre out to sea.

Behind us, I can make out the tall, green mountains of Kadavu, the nearest island. Here on its remote north coast there are no roads, just a handful of traditional villages built among the jungle ... and certainly no hospital. There's no-one around us for 50 kilometres, and I'm surfing a break that's only been sampled by a handful of surfers staying at the resort I'm at. Whoever said surf exploration died out with the 20th century obviously hasn't been to Kokomo Private Island.

But then, that's how life seems to be in this part of Fiji. I'm staying on my own private island resort reachable only by seaplane (or helicopter) flown by pilots in bare feet; and the only company we've got round here – aside from the odd tiny village, on its own tiny island – are the cast and crew from a French version of Survivor living out Robinson Crusoe fantasies on a tiny island just north of here.

Many travellers think of Fiji as one island destination, but there's actually 333 islands here. This one – Kokomo Private Island (on Yakuve Island), the latest, greatest offering to Fiji's impressive stable of private island retreats – is 45 minutes flying time from Nadi International Airport, or 25 minutes from Suva's. This means that though it feels as far-flung as the South Pacific gets, you can actually get to Kokomo in a little over five hours from Sydney or Melbourne.

The island is protected by the world's fourth largest reef – the Great Astrolabe – and nowhere in Fiji offers better diving or fishing. I'm no diver, but Kokomo Private Island feel so strongly about their marine offerings they offer open-water introduction dives (Discover SCUBADiving) with their room rates (don't dive and you're ripping yourself off). There's more than 40 dive sites along the eastern and western sides of the reef – none of which can be accessed by any other resort; and most can be reached in less than 20 minutes by boat.

After a short briefing and a dive in the shallower waters off the resort's horseshoe-shaped bay, I'm taken to a site that allows us to dive along a dramatic drop-off of the Astrolabe. There's no-one around, just a whole lot of royal-blue ocean which, apparently, teems with reef sharks. And this is what I must remember: 1. Don't hold my breath ... my lungs might explode. 2. Sharks are my friends, the calmer I am around them, the longer I'll get to spend with them. And; 3. If I panic and scramble to the surface, 12 metres is deep enough to give me the bends (a life-threatening decompression sickness).

But the clarity of the water calms me – I can see beyond 50 metres so nothing can sneak up on me. Instead when eagle rays, turtles, reef sharks and a solitary manta ray pass close by, I feel like I'm sharing the ocean with them on my own terms (later, I'll see a two-metre-long silver tip oceanic shark as I fish ... and I'll prefer my position on top of the sea). Kokomo Private Island encourages first-time divers to go beyond the shallows and out to these depths (up to 12 metres), so we can see what lies beneath for the first time. Though round here, the most revered sea creatures often pass by the beach at the resort – between May and August, fevers of 20-or-so manta rays swim by, allowing guests to snorkel or dive with them for hours at a time; while humpback whales pass close by between June and October, and resident green and hornbill turtles live nearby.

For a resort with this sort of room rate – and one that was designed to serve as the legacy of a billionaire – Kokomo Private Island somehow manages to feel, and look, under-stated. Australian tycoon Lang Walker intended to build just three villas, now there's 21 beachside villas and five private residences. But while they're huge, and they sit right on the sea (with backyard infinity pools, should the ocean not prove wet enough); their decor reflects the traditional style of Fijian dwellings (simple open-plan rooms and roofs of woven pandanus). Though it's the resort's secondary restaurant and bar, Walker'd'Plank (you can choose to forgive Walker his one brush with megalomania, or not), which epitomises Kokomo Private Island. Originally planned to have nothing more than a beach umbrella with an esky tucked into a tiny cove by the arrival jetty, Walker'd'Plank has been cobbled together with driftwood and odd items bought from a boat yard in Suva. I sit watching baby black-tip reef sharks feed in the shallows in an open-air eatery built among a boardwalk a metre-or-so above the ocean, on old pink and blue chairs beneath rusted propellers and Japanese glass fishing floats in a setting lifted straight out of a Jimmy Buffet song (Margaritaville: eat your heart out). There's no menu here, instead head chef Caroline Oakley asks what I like, tells me what's been caught, and we work it out from there. We settle on a combination of Spanish Mackerel sashimi, Fijian kokonda (raw fish cooked in lime juice, covered with coconut milk, onions, cucumber and tomato) and tempura octopus.