The River Postman, Hawkesbury River: This is the world's best postal route

An isolated hamlet of the Hawkesbury River that can be reached only by boat.Credit: David Whitley

From the wharf comes a call. "You haven't come across any pirates, have you?" shouts the president, from his waterside throne. John Carrick, ruler of the self-styled Republic of Milsons Passage, has to protect his people from brigands. But there are no worries this time – it's just the mail being delivered.

The presidential sash goes across the presidential shorts and T-shirt, and a little white dog by his side stands guard. "He's a specially bred albino dingo who helps keep the sharks away," the big chief says.

The eccentric "republic", despite the blue mudcrab flag waving proudly over the boat sheds, is not likely to become a major player on the world stage any time soon. It is an isolated hamlet of the Hawkesbury River, just to the north of Sydney, and cannot be reached by road. That's why Australia Post has to use a novel approach – and the mail has been delivered by boat for more than 100 years.

The flooded river valley is surrounded by thick green bushland, mangroves and sandstone cliffs.Credit: David Whitley

As mail runs go, it's an absolute beauty of a gig. There are only seven stops to deliver to, and they're spaced along a flooded river valley surrounded by thick green bushland, mangroves and handsome sandstone cliffs.

The catamaran putters along for about three hours, doubling up as a pleasure cruise for most of those on board. But despite having passengers to feed and entertain, the crew members know that their first priority is to get letters and parcels to tiny communities that are otherwise cut off.

The cruise – and mail run – starts from Brooklyn, where trains from Sydney and Newcastle pull in. The neighbouring rail bridge crosses the river, and gives those living on the settlements on either bank a connection to normality. But many smaller settlements – generally just a handful of houses, many of which are waterside holiday homes that have been passed down through generations – can be accessed only by boat. Aside from the houses that have been grandfathered in, there is a smattering of artists and writers who love the isolation and have set up home on the wild banks of the Hawkesbury.

The bridge that connects the isolated hamlet to the rest of the world.Credit: David Whitley

Throughout the journey, skipper Randall Ferrington holds court on the historic oddities in the river. There's the wreck of the HMAS Parramatta, Australia's first ever warship, which was later reduced to the indignity of hauling coal before it sank.

There's also Milsons Island, which is now a sport and recreation centre for kids, but was once used as the testing centre for myxomatosis before it was released across Australia to keep the rabbit population under control. During World War II it was turned into a rehabilitation centre for soldiers recovering from their wounds. "They recovered quicker here, for some reason," Randall says. "Must have been something to do with the view."

There followed yet another incarnation as a minimum security prison – and Randall used to do the transportation runs there, so he's got plenty of stories of people who tried to escape for a night out in Sydney. One had the misfortune of flagging down an off-duty policeman while trying to hitch a lift, while others who stole canoes to escape were caught out when they were notably muddier than the others the next morning. It turns out that wading through mudflats leaves you with a few incriminating signs …

While the passengers admire the bulging rock faces and eucalypt cover, the crew have letters to deliver. And it turns out that each drop-off works slightly differently. Some have boxes by the shore, which individuals come down to later in the day. Other communities use a rota system – one person comes to meet the boat, then distributes everything to the other houses later on. "That usually turns into morning tea, then lunch, then afternoon tea …" Randall says. "It's not exactly a hardship task."

There's even one fisherman who lives deep in the mangroves and doesn't really care about the human company. He has put a hook on a wooden pole in the middle of the river. If he's got mail, they can just leave the bag on the hook.

But elsewhere, there is usually a canine greeting party for the crew member who has to leap off the boat and drop off the goodies. Never in the history of mail delivery has a postie had to deal with a collection of less threatening dogs. At Marlow Creek, a slightly portly little lady comes wandering down from the cottage at the top of the hill. "Her name is Boots," Randall says. "And she loooooves her Anzac biscuits." Sure enough, the woman with the mail bag has a biscuit in her other hand, and Boots merrily takes it from her. The Hawkesbury Riverboat Postman always makes sure the special deliveries are taken care of …

Details: The Riverboat Postman (riverboatpostman.com.au) departs from Brooklyn at 10am, every Monday to Friday. Tickets cost $50.

See also: Ten of Australia's greatest boat trips

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