Where in the world would BBC Television choose an exotic island to film a castaway survival documentary?

Logic suggests it would be an undiscovered paradise of timeless beauty and simple pleasures - a world of its own on a lonely island far from civilisation. A world of the imagination replete with lush forest glades, hot springs, deserted white-sand beaches and fine seafood dining venues.

Welcome to our world! The recent BBC Castaway series was filmed on Harataonga Beach on the east coast of Great Barrier Island, Auckland's best- kept tourist secret.

Remarkably, New Zealand's fourth largest land mass has managed to slip beneath the radar. Our own treasure island is just a 30-minute flight or 4-hour ferry ride from the city but most Aucklanders have never made their acquaintance with The Barrier, as locals call it. Until a recent long weekend I, too, was a stranger to its golden sands and kauri dams, hot springs and chevron skinks.

With a small group of kindred spirits I begin my journey of discovery on the SeaLink vehicular ferry. The Island Navigator boasts a bar, cafe, two movie theatres and regularly attracts our friendly next of fin, bottlenose dolphins, so it doesn't seem too long before the volcanic peaks of the "Guardian of the Gulf" hove into view.

Waiting at Tryphena Wharf is the island transport guru, Steve Billingham, who conveys us to a leafy eyrie called Shoal Bay Lodge. This solar-powered eco-lodge is surrounded by native bush. From the balcony I gain my first impressions of The Barrier as a human habitat, while watching satiated tui trilling their hearts out in a nearby kowhai tree.

The beautiful bay is edged with traditional Kiwi baches tucked in sheltered coves where gnarly pohutukawa trees in crimson glory tumble into a sparkling sea. A few modest houses are partially hidden on bush-shrouded promontories accessed by a 4WD track. This is the pattern of settlement throughout the island.

Claris is the nearest thing to a commercial centre. There are no banks, offices, high-rise buildings, highways or traffic jams. The Barrier is simply the ultimate refuge for hardy, self-motivated, independent lifestylers who draw their energy from solar cells, batteries, wind turbines and generators.

But the true charm of the island lies in its friendly, outgoing people. Sadly, they are diminishing in numbers as families sell and move to the mainland for access to secondary schooling. The current permanent population is just 750. One place to meet local characters is the Currach Irish Pub in Tryphena, where we enjoy a fine meal of chowder and tarakihi in the company of a convivial group on a weekend fishing excursion.

Local identity Chris Olivier, skipper of the good ship Sundancer, is our host next morning as we cruise the deeply indented west coast. His Ultimate Tour has us squeezing through the Junction Islands and Man of War Passage to enter Fitzroy Harbour, sustained by a lively commentary, excellent wine and kebabs.

I fall in love with the scenery; craggy headlands plunging into deep blue water fringed with waving kelp beds - a sure sign of The Barrier's scuba diving and deep sea fishing potential. Lush forest reaches down to wave-washed reefs. Gannets rocket into the sea and emerge with shiny baitfish in their beaks.

Nosing into the Wairahi Bay wharf, we meet Sven Stellin, the irrepressible manuka oil guru, who explains that his rustic retreat is, "either a paradise or a prison". We soon learn the halcyon days of summer mean hard labour for him. He gathers 700kg of manuka leaf material for each processing cycle in the distilling plant, producing a litre of antibacterial essential oil.

The plant recycles the island's waste oil to fuel the furnace and produces some nifty Barrier Gold products that prevent mosquito bites and sunburn. Sven regales us with what he calls his "propaganda and bull dust" and displays three wine goblets that cause a flurry of excitement among his audience. That is until we realise they contain pure extract of manuka oil, kanuka oil and also diesel oil, which is blacker than the Guinness in Tryphena's Irish Pub.

Conservationist Tony Bouzaid is passionate about native flora and fauna and his Glenfern Sanctuary tour is one of the island's highlights. It begins with a hill climb in Tony's all-terrain ex-army Unimog, enlivened by overhanging fern fronds swishing into the open-sided vehicle.

From Sunset Rock we view the full extent of Port Fitzroy and pinpoint the course of his predator-free fence. Tony has planted 9000 native trees and maintained 500 rat and feral cat traps in recent years. The Barrier is mercifully free of possums, stoats, ferrets, weasels and hedgehogs.

Walking along the Kauri Trail I'm staggered at what this modest man has achieved in his labour of love during 18 years of supposed retirement. Some 40 different native species have been planted and the first stage of forest is well advanced. The "piece de resistance" is a suspension bridge that carries us into the canopy of a 600-year-old kauri tree.

Driving back down "State Highway One" as Aotea Rd is called, we are blown away by the stunning east coast beaches. Harataonga Bay, where the BBC castaways squabbled and scrapped, looks so inviting with its protective island and swathe of sand. Awana, Kaitoke and Medlands beaches are glorious sweeping arcs of sand washed by the island's surf.

Picturesque Medlands Beach provides a dazzling view from the balcony of Mount Saint Paul Lodge where we dine tonight. Manager Ivan Manaway is an island identity who keeps a number of balls in the air to keep the tourism business humming. His wife Chris serves up superb seafood cuisine and excellent wine with which we toast the All Whites who have just qualified for the Football World Cup.

Our Sunday morning begins with pure relaxation in the Kaitoke Hot Springs among towering nikau palms and ponga groves. The springs are a legacy of the island's volcanic origins. The bush offers up a chorus of birdsong and dragonflies hover in mid-air.

A relaxed lunch on the balcony of Great Barrier Lodge is a fitting way to round off a most enjoyable long weekend. It is a scene of absolute peace and tranquillity. Beautiful bush-fringed Whangaparapara is the quintessential Barrier harbour with an unfathomable X-factor quality that takes us to another world, far removed from the cares of city life.

We have a FlyMySky plane to catch but guide Steve still has a few surprises. The first is a hair-raising ride on his Crazy Horse tricycle motorbike over the hill to Okupu Bay to view a pod of dolphins. Steve offers visitors the joy of feeling the wind in their hair on a World Tour of The Barrier, rather like the Billy Connelly TV series.

We visit the quaint Milk, Honey and Grain Museum to soak up the island's fascinating history, followed by a latte at the lively Claris Texas Cafe. It's every bit as good as coffee in the trendy Queen St cafes.

My three-day sojourn has clearly shown that The Barrier offers something for everyone; from those little touches of luxury to the wide open spaces for people seeking solitude and adventure.

It's an island of opportunity - a place for satisfying dreams. Break away to The Barrier, meet the characters, feel the independent spirit and, like me, you are sure to take away a host of good memories.

Fact file

Great Barrier Island is 90km northeast of Auckland. SeaLink ferries depart from the Jellicoe St terminal six days a week in summer, taking 4 hours to Tryphena Harbour.

Flymysky and Great Barrier Airlines make regular flights to Claris Airport on the island, leaving from the Auckland domestic terminal. Flight time is 35 minutes.

Accommodation, ranging from backpackers to luxury lodges, is available in the main settlements and port villages. Transport between the settlements is easily arranged with rental vehicles and taxi services available.

Great Barrier Island Tourism provides shuttle services and tours throughout the island.

* Paul Rush travelled to Great Barrier Island courtesy of SeaLink and Tourism Auckland.