It never occurred to me that laundry, even in all of its myriad, strung-out forms that occur throughout Italy, could be the subject of such mutual delight and admiration. But, as I gaze up at the assemblage, which no doubt will take an eternity to dry in the middle of this Venetian winter, I notice that the items, back-lit by the weak sun, are all perfectly pegged and, at such a height, skilfullyarranged. "What a good time to be in Venice," the woman says. "You can still hear your footsteps at this time of the year."

It is one of those brief, amiable and apparently, increasingly rare, encounters between locals and tourists; one probably only possible because it occurred well away from the city's ever madding crowds and a time of the year when the collective mood of the Venetians is much less strained

Such a fleeting yet memorable moment can nearly make one forget the near existential threat to Venice's future of which no prospective, caring visitor should be unaware.

THE SINKING FEELING: VENICE UNDER SIEGE

It's difficult to conceive of any city on Earth that has engendered so much ardour, and simultaneously, so much alarm. Much concern has been expressed, after all, at the fact that Venice is gradually sinking, centimetre by fearful centimetre, into its own muddy underbelly. But its more immediate, or at least parallel, challenge, is how it confronts the combined weight of up to 27 million tourists a year (estimates of the number of visitors a year vary greatly) under which it is also being submerged.

In the summer high season visitors outnumber locals 20 to one. In the past year or, many of Venice's 55,000 citizens have begun to actively revolt against some of the 100,000 tourists who descend on the city daily. Of that number, 30,000 of the visitors are cruise ship passengers, most of whom descend on an already crowded St Mark's Square, spending little or no money in the city before returning to their vessels.

The concern has reached such a point that it has even been suggested that turnstiles be installed at the six entry points to St Mark's Square – where day-trippers would be charged a fee to control crowds and collect the revenue needed to maintain the crumbling city. Even a ban on suitcases, whose wheels create noise pollution in the city's narrow streets, driving the Venetians to despair, as well as damaging paving and bridges, was contemplated a few years ago.

Elsewhere in Italy, the custodians of the Cinque Terre considered reducing its annual visitor numbers from 2.5 million to 1.5 million through the imposition of hefty fees for the pleasure of accessing the tracks that pass along its famed jagged coastline.

But destinations which impose limits on tourists can succeed in deterring greater number of visitors than they had intended. In light of the possible impact of such measures, even at their mere suggestion, several Cinque Terre tourism websites now carry disclaimers stating that no such restrictions are in place.

There is no question that the pressure is building on some of the most cherished places on the planet, something which will likely transform the nature of tourism. Earlier this year, Venice came perilously close to being placed on UNESCO's list of endangered World Heritage places, with the city having been issued a warning to address the problem of too many large cruise ships visiting the lagoon and disgorging their passengers. However, the city's mayor is reportedly showing no intention of acceding to UNESCO's request.

One could, of course, be kind to Venice by not visiting her all. But that would directly disadvantage the Venetians who, despite their dissatisfaction at the tourist hordes, rely on them for their livelihoods. Despite the ever-rising tide of visitors, Venice's population is at a historical low with one expert calculating that, should the pace of decline continue, by 2030 the city will have zero citizens.

Nowadays travel for a worryingly large number of tourists can appear to be a matter of merely turning up without any consideration of the the impact of doing so. In many parts of the world, travel has become a pursuit divided between the thinking and the unthinking, with the former engaged in a constant game of evading the latter. And, having been aware of Venice's visitor vicissitudes before my arrival earlier this year, I began to wonder how the tourist in some small way could be more considerate during his or her interlude in the city.

BEING NICE TO VENICE: AN OFF-PISTE TOUR

Despite its mayoral intransigence, the City of Venice in recent years has launched a "Detourism Venice" campaign, designed to promote the notion of slow and sustainable tourism by encouraging visitors "to go beyond the usual tourists sights" well away from the "well-trodden tourist routes". That is, where the clothes lines begin to appear.

By doing so, there is an opportunity to experience Venice a little like those last remaining Venetians do. You can easily download the City of Venice's self-guided "Art and culture itinerary of Classic Dorsoduro" walking tour, saving a small fortune on the cost of a private guide, as well as two other tours of the sesiteria, or districts, along with San Polo, over the internet. A magazine, in both Italian and English, is regularly published, detailing all of Venice's under-visited attractions, as well as a weekly newsletter.

Dorsoduro, in the south-west of the city, features some of Venice's most important art and cultural attractions but it's also one of its less frequented areas.

We decide to test the City of Venice's notion of detourism and start our tour at the busy and less-than-lovely Piazzale Roma at the edge of the city beyond the train station, crossing Tre Ponti (Three Bridges), then heading deep into Dorsoduro.

As my self-guided tour points out, there is only one piazza in Venice and that is the over-patronised Piazza San Marco. All of the other squares in Venice are referred to as "campo", meaning "field", a reference to the fact that until 1500 there were few paved areas in the city. Already, we sense we're well off-piste, or as much as you can ever be in a city as relatively small as Venice.

When I emerge into Campo Santa Margherita, a surprisingly spacious square full of restaurants, cafes, gelataria and popular with students from the nearby university, I sense I'm the only non-Venetian in the whole square.

Its most eccentric point of interest is Scuola dei Varoteri, a lone building which was once the headquarters of furriers who specialised in fine Siberian squirrel fur used to decorate the garments of the Venetian nobility.

Further along is the Church of San Pantalon which boasts its own version of Rome's Sistine Chapel with its entire ceiling covered by a nearly 500-square-metre painting, Martyrdom and Glory, by Giovanni Fumiani, a noted Venetian painter of the Baroque period. It took the 17th-century artist 20 years to complete the painting. During our visit to the church my partner and I are the only people inside the darkened church, aside from a lone attendant keeping watch on the church and providing change for the coin-operated timed lighting system that allows for sections of the painting to be illuminated.

We press on, crossing this way and that, darting across bridges small and large, passing through dank, narrow, stooped passageways that suddenly emerge from nowhere, never quite certain as to where we are and forever on the verge of being lost, all which in themselves are among the great pleasures of any visit to Venice.

Near the Church of San Pantalon is another of Venice's lesser known charms. Heading in the direction of Accademia and moored near Ponte dei Pugni is a fruit boat – a floating green grocer – a once common feature of Venetian life. Further on, we pass through Campo San Barnaba, close to Ca' Rezzonico, one of the few Venetian mansions open to visitors.

The building was commissioned in 1649 but wasn't completed until  more than a century later due to the financial woes of the original commissioning family. Its restored interiors feature gilded ebony furniture, velvet and damask, the alcove, and fine paintings by Canaletto. Beyond Ca' Rezzonico, our tour commands us to "go straight down Sotoportego del Casin dei Nobili and Calle Toletta as far as Ponte delle Maravege" . We continue and cross yet another bridge until we reach a canal called Rio de san Trovaso, named after a 15th-century church by which it passes.

The Church of San Trovaso is home to one of the rarest of Venice sights: a grassed square, a living echo to the green field-like campos of the city's distant past. As we enter the church, we discover that we're again the only tourists on hand and are able to view Jacopo Tintoretto's Last Supper, painted between 1564-66 in private. The church is also the venue for Chrysogonus on Horseback, a 15th-century work by Michele Giambono. One of the church's neighbouring buildings is an ancient Venetian boatyard where gondolas are still built and maintained.

There is still much to see but, as the shadows descend over Venice like a Siberian squirrel-lined coat, on this wintry afternoon, it's spritz o'clock. It's the time of the day when Venetians pause for their beloved year-round fizzy aperitif. One of Venice's few bargains at as little as  $5 a glass, the best places to enjoy it  are right here in the backstreets of Dorsoduro in an ordinary bar or cafe shoulder-to-shoulder with the Venetians.

ARRIVEDERCI, LA SERENISSIMA: ONE LAST LOOK

If Venice can be a hard place to visit, especially in its high season, its lowest point is that it remains an even harder one to leave, especially when experienced at its more subdued times of the year. Perhaps the world will need to be shocked into caring more for such a precious place,  with UNESCO eventually placing it on its most endangered list.

For now, on my last day, standing near the Bridge of Sighs in the middle of Venice's annual Carnevale, with which our visit coincides, the City of Venice's Detourism campaign strikes me as the most hopeless, albeit noble, of gestures. A group of tourists has surrounded one of Carnevale's brilliantly costumed paid performers, taking photographs in silent awe on their iPhones and the odd SLR. In their dull black ribbed parkas, these gawping tourists resemble a large flock of dusty sparrows encircling a lone posing peacock, a metaphor, of sorts, for the state in which Venice finds itself. But, a bit like a peacock, there is a certain pride to have at least tried to show some care towards La Serenissima – its now near redundant nickname meaning "most serene" – and to have shaken off at least some of the sparrows.

CANAL THERAPY: FIVE WAYS TO CARE FOR VENICE

VISIT IN THE LOW-SEASON

Winter, perhaps surprisingly, is commonly regarded as the best time to visit Venice. Flood-prone it can be but the crowds are far smaller and the Venetians, including the gondoliers, are more relaxed and appreciative of tourists bolstering the economy at a quieter time of the year.

STAY A NIGHT OR MORE

Many of Venice's visitors are day-trippers who pour into the city but fail to pour little or any money into the coffers of the tourism industry. If you stay overnight or longer you are helping Venice's economy by paying for accommodation, eating at restaurants and patronising its attractions.

DRINK THE TAP WATER

Discarded plastic water bottles are damaging to a fragile environment like Venice and their contents, as is the case elsewhere, are grossly overpriced. Venice's water is potable with the City of Venice encouraging locals and visitors to drink it at their hotels as well as from the many ancient water fountains.

HIRE A PORTER

You will find luggage porters waiting around the railway station. The wheels of their trolleys are rubberised and therefore more forgiving to footpaths and bridges. On departure,  your hotel can also call them for you for the return trip.

TAKE A TRAGHETTO

Venetians know that the best way to beat the crowds, especially on the city's clogged bridges, is to take one of these gondola "taxis" from one side of the Grand Canal to other. Not only are they non-polluting, there are a bargain when compared  with motorised vaporetti (water taxi) and tourist gondolas, costing less than $2 for the short ride.

ENOUGH ALREADY: FIVE  PLACES WHERE VISITOR NUMBERS ARE LIMITED

BARCELONA, SPAIN

The Catalan capital receives more tourists a year than Venice. After complaints from its citizens, the city's burghers have taken action against cheap online accommodation providers which are attracting too many visitors into the already crowded central part of the city. See barcelonaturisme.com

CINQUE TERRE, ITALY

One of Italy's most famous and spectacular attractions is seeking to dramatically reduce its annual number of visitors from 2.5 million to 1.5 million, with tickets sold online for access to the tracks that pass along and above its famed rugged coastline. See cinqueterre.it

MACHU PICCHU, PERU

Largely at the behest of UNESCO concerned about the impact of tourists, a maximum capacity of 400 visitors a day, divided into two groups of 200 people, is now permitted to visit the famed lost Inca city of Peru. See peru.travel

SANTORINI, GREECE

The idyllic Greek island has declared it will limit the daily number of cruise ship passengers it receives each year. It will mean that the number of visiting passengers will be more evenly distributed over the course of a week. On some days 10,000 people currently descend on the island from ships alone. See santorini.net

BHUTAN

The tourism industry of the landlocked south Asia Kingdom of Bhutan is based on a philosophy of sustainability with tourists required to spend a minimum daily amount on accommodation, food, transport and attractions before they are allowed to visit. See tourism.gov.bt

TRIP NOTES

MORE INFORMATION

veneziaunica.it

railbookers.com

qantas.com

TOURING THERE

Railbookers is a British-based tour operator specialising in tailor-made packaged holidays by train around Europe and other parts of the world, including Asia and the US. It can arrange all itineraries, ticketing and accommodation bookings. See railbookers.com

GETTING THERE

Qantas operates daily flights to London Heathrow from Sydney and Melbourne via Dubai, with air connections  from Heathrow to the major European capitals. See qantas.com.au

STAYING THERE

The four-star Hotel Canal Grande is just across the Grand Canal from Santa Lucia Railway Station, where most visitors arrive in Venice. Doubles start from about  $215 in the low season. See hotelcanalgrande.it

Anthony Dennis travelled as a guest of Railbookers and Qantas.