Welcome to the suburbs

Swampy is the word that summed up last weekend in Cairns, Australia's most wayward city. Each day, the good and the great of Britain's travel industry splashed across the vivid emerald marsh surrounding the city's convention centre, where the Association of British Travel Agents (Abta) was meeting for its annual get-together.

The happiest people in town were the cab drivers, who cashed in on the relentless rain to make an out-of-season fortune. The lippiest people in town were the tourist representatives from Perth, Melbourne and Adelaide, who delighted in pointing out that their cities were enjoying an early southern summer of lavish sunshine. And the drippiest people in town were those who did not notice that, if you delve deeply enough into this tropical suburbia, you can construct a city-dweller's Crocodile Dundee experience.

Cairns sprawls around a bay in far north Queensland, as close to the Equator as is the Caribbean island of Antigua. This location reduces the seasons to a maladroit and unmatched pair. The Dry, which corresponds with our northern summer, gives way at the end of October to The Wet, which drenches the Queensland coast, and any stray travel delegates, right through to April. It's warm rain, mind - hot is a given at sea level in the tropics, so you may explore the urban outback fearing nothing more uncomfortable than warm mud.

Road names in Cairns hint, mostly, at the adventure that awaits. The Captain Cook Highway stretches heroically onward from Upward Street. Close by, a collection of tropical fruit basks in names such as Avocado Close, Lychee Street and Papaya Close. So it was a mite disappointing to find myself in a suburb called Bungalow.

Cairns is a funny place, a safe blend of well-to-do suburbs spiked with the excitement of being a real travellers' centre. It is Australia's answer to those great travellers' nodes, such as Istanbul or Kathmandu or Cuzco, where every backpacker arrives, sooner or later. Like those places, it boasts plenty of cafes offering Internet access and banana pancakes. Unlike them, Cairns is not a city steeped in culture and history. As far as the Europeans are concerned, the place was unknown until Captain Cook sighted the bay on Trinity Sunday, 1770. Another century elapsed before any kind of settlement was established, and only when the international airport opened in 1984 did development take off.

As soon as you arrive, you find yourself surrounded by people trying to sell anything from scuba diving lessons to a "rainforest adventure". They have a point in tempting you out of the city, because Cairns lacks even a beach. Instead, there is a tidal mudflat that looks plain swampy.

My personal urban rainforest adventure began to take shape at the Flecker Botanic Gardens, an effusion of greenery for which the word "prolific" is inadequate. An explanation shows how aboriginal people used plants for food and medicine. And, the Guided Walk, or squelch, in my case, leads through an outrageous tangle of flora that turns out to be entwined with the development of Australia. Exhibit 1: the breadfruit tree. Not the most beautiful tropical plant, but what a history. It was to procure the edible variety of the breadfruit tree that Captain Bligh and his bounteous crew were dispatched to Tahiti. The plant, you learn, reproduces only through cuttings. The mutiny occurred at end of the necessary propagation period by which time the sailors had taken a shine to Tahiti and its people, and were reluctant to leave.

"Blight", as he is called in the guide, then sailed in an open boat to present-day Jakarta, and later became governor of the colony of New South Wales.

Now, as then, the north of Australia is home to all kinds of natural nasties. "Intense stabbing pain - symptoms may persist for some months", warns a notice in front of a cage containing the Queensland stinging weed. This malevolent member of the nettle family contains a virulent nerve poison, and the exhibit enables you to know at least one of your enemies. An aesthetic antidote appears in the shape of the glowing Torch ginger, a scarlet beacon even through the drizzle. But there are many other examples of threats to health, preserved in glass jars in the town's best museum - just a short, safe stroll away.

At the visitor centre of the Royal Flying Doctor Service, a rogues' gallery of taipan snakes, redback spiders and sea wasps are among the creatures that could bring an early end to you and your travels. For someone falling ill in the wide open spaces of Queensland in the Twenties, the only hope was to start pedalling. This fascinating exhibition includes a working pedal radio, where a pair of bicycle cranks is harnessed to generate electricity to summon the flying doctor. But this was no passing phase; in 1999, the RFDS is more active than ever.

The wardrobe into a wilder natural Narnia stands adjacent to the gardens. The Whitfield Range begins as a spur of rock shooting northwards, miraculously clad in a pretty good approximation to virgin rainforest. Man has intervened but in a curious, and beautiful, fashion. From a distance, the green carpet created by some splendid palms as they march up the hillside is speckled with red ochre. These turn out to be Royal Ponsiannas that have run wild, escaping from suburban gardens to become feral members of the Bush.

You clamber up the hillside less elegantly than the trees, heckled from time to time by an orange-footed scrubfowl, whose main attributes are a Napoleonic skull and a coarse screech. But the reward is a view that is half sublime, half ridiculous. The good part, with your back to the ocean, is to see how the rainforest, once released from the city, explodes over the mountain ridges. The silly portion comprises Northern Exhausts and O'Brien Windscreens, two of the more prominent members of a motor trade that is sprinkled along Captain Cook Highway.

Beyond them, man and nature tussle over the mangrove swamp that thinks it's an airport. The local planners boast that the land on which the runway stands has been reclaimed - a curious phrase, suggesting that those darn mangroves had overrun the previous airfield.

During my descent to continue the investigation, I became aware of an intermittent snuffling in the undergrowth. The bouncing, bulbous creature responsible was a swamp wallaby, enjoying The Wet more than the rest of us. But he looked more frightened of me than me of him.

At the Abta convention, the Manchester Airport people were joking about asking the environmental protester Swampy to open the new runway. Cairns airport has gone one better, by creating a Swamp Trail.

This does not involve tunnelling beneath the runway, but a raised boardwalk that sends you hovering three feet above the sort of gunk you find when runways are being gouged out of fields. But this is real mangrove swamp, as the slender trunks reveal. They are clad in fleshy bark that dries to a porcelain white because of the salt sucked in from the seawater that washes over them.

Among the two dozen species of mangrove are some which sweat salt through their leaves and others which rise from a squabble of roots to form the arboreal equivalent of flying buttresses. The mud is punctuated by "pencil roots", sticks that allow the plants to breathe something other than saline solution, and "knee roots" that lope in double-joints along the surface while crabs scuttle sideways. This whole surreal scene is made all the stranger by the occasional roar of a stray Boeing, and a series of sickening squelches.

These turn out to be the fatal interaction between cars speeding along the airport road and cane toads. This imported species flourishes so well in Queensland that it can afford to have members flattened by the million on the highway. The creature even takes revenge from beyond the Tarmac grave: animals and birds tempted to treat the two-dimensional toad as carrion find out to their cost that the amphibian has a poisonous gland.

None of which could temper a hunger induced by a day in the Outback. I wandered into town past the backpackers' hostel and sheltered from the rain under the awning of the Red Ochre Restaurant. The meat served in this modern Australian bistro was exquisitely tender and tasty, washed down with a venerable Shiraz that complemented the young flesh.

No wonder that wallaby - let's call him Swampy - looked so scared.

Simon Calder paid pounds 931 for a curious itinerary to Cairns and back, via Madras, Mumbai, Singapore, Darwin, Jakarta and Feltham, booked through Quest Worldwide (0181-547 3322). He paid pounds 7 per night at the McLeod Street Youth Hostel in Cairns.

Cairns contacts: Flecker Botanic Gardens: Collins Avenue; Royal Flying Doctor Service, 1 Junction Street; Whitfield Range Environmental Park, entrance on Collins Avenue; Red Ochre Grill, 43 Shields Street, Cairns.

For more information on Australia contact the Australian Tourism Commission, Gemini House, 10-18 Putney Hill, London, SW15 or call 09068 633235 (50p/ min)for a brochure