Other than a 65-mile, dead-end stretch to the town of Nauta, there are no roads leading in or out of the Amazonian city of Iquitos, Peru. While its small airport has direct flights to Lima, most goods are shipped in or out by river. The shortest distance would be upriver to Yurimaguas, a roughly 4-day journey that still requires a drive over the Andes Mountains. For larger ocean-going vessels, it’s a long journey. The mouth of the Amazon, where the river meets the Atlantic, is more than 2,300 miles away.

“I can get in my canoe and after a few minutes of paddling it’s like I’m in Pacaya Samiria, a nature reserve,” says artist Mariem Valdez Torero, who lives on a floating house docked on the Itaya River near Iquitos’ malecón (jetty). “The colourful landscape is reflected on the water. The sound of the birds replaces the noise of the streets and I forget all about the sounds of the moto-taxis.”

It’s often a special circumstance, such as a surplus of a particular resource, which helps offset logistical issues and pushes a remote settlement to tens or even hundreds of thousands of citizens. Iquitos, with a population approaching 400,000 according to the latest census, fits into this category. Founded as a Spanish Jesuit mission in 1757, Iquitos ballooned during the Amazon rubber boom (1880-1914). It was a period of great wealth, where luxurious foreign products were imported. While other rubber boom cities along the Amazon have been connected by roads and have continued to grow since rubber production shifted to Malaysia a century ago, including Manaus and Belem in Brazil, Iquitos’ seclusion has left growth static, minus a few bumps from other minor booms from oil, tourism and the drug trade.

I can get in my canoe and after a few minutes of paddling I’m in Pacaya Samiria, a nature reserve Mariem Valdez Torero, Iquitos

The Amazon river at the port in Iquitos, Peru. Photograph: Alamy

Rugged, undeveloped regions host some of the remotest cities. With natural obstacles like mountain ranges or intense weather systems, other settlements are deterred from forming nearby. Take for instance the Russian city of Petropavlovsk-Kamchatsky, surrounded by volcanoes on a distant peninsula between the Bering Sea and Sea of Okhotsk. It is closer to Alaska and North Korea than Moscow, 4,204 miles away, and, like Iquitos, there are no roads leading to it. It depends on imports of fuel, food and equipment, though it has managed to grow to a population of around 180,000 because of its ties to timber and fishing industries.

Population centres tend to get fewer and more spread out the closer one goes to the poles. Cold weather and long winters hamper farming, limiting communities to small, mostly indigenous, hunting and gathering groups that rarely top a few hundred families. Places like Nuuk, Greenland, the world’s northernmost capital, or Barrow, Alaska, above the Arctic Circle and the northernmost point in the US, are a few of the exceptions, though don’t expect to see skyscrapers. Cities with populations above 10,000 people are quite rare here.

If physical distance between cities is the defining factor in remoteness, some of the greatest spaces occur in the Pacific. Hanga Roa, on Easter Island, might be thousands of miles from any significant settlement, though it only has a few thousand residents, hardly qualifying it as a city. Honolulu, Hawaii on the other hand, has a population similar to Iquitos, but, aside from other towns in the Hawaiian archipelago and a few tiny atolls, it is more than 2,300 miles from San Francisco, the nearest major city.

One downfall of remoteness can be the cost of living. Despite being a part of the United States, where goods in general tend to be lower cost than other parts of the world, Honolulu is expensive. With no roads off of Oahu and only a few specialised products produced on the islands, importing goods is costly. According to a 2014 Kiplinger report, the cost of living is 69 percent higher than the US average. Everything from electricity and petrol to the eggs in a loco moco are significantly higher than the US mainland.

Houses in Nuuk, Greenland, the world’s most northerly capital city. Photograph: Alamy

So if remoteness can be measured with a single number, related to distance, Honolulu looks like the winner. But more than eight million visitors came to the Hawaiian Islands in 2014 and there are hundreds of flights daily that connect it to the rest of the world.

Despite their out-of-the-way locations, Australia and New Zealand are home to numerous large cities. More advanced communication technologies and the increasing ease of importing or exporting physical goods have helped free the countries from the tyranny of distance.

Yet, in Australia, most large cities can be found along the east and south coasts, away from the interior, the bush, which dominates the majority of the country. Then there is Perth, with a metropolitan area of more than two million people, way on the other side of the outback from Sydney, 2,045 miles away. Geographically it’s actually closer to East Timor (1,731 miles) and Jakarta, Indonesia (1,865 miles). There’s no city of comparable size anywhere in the world that’s so remote.

The city’s population exploded during a late 19th century gold rush, then surged again after the second world war following an influx of European immigration and increased mining activity. Yet development was restricted to just that corner of the country. The nearest city of at least 100,000 people is Adelaide, a distance of more than 1,300 miles.

Perth is so isolated that it is quicker, easier and cheaper to fly to Bali then to fly to the east coast Lacy Gow, Perth

A cyclist rides along the Swan River in Perth, Australia. Photograph: Bloomberg via Getty

“Perth is so isolated that it is quicker, easier and cheaper to fly to Bali then to fly to the east coast. To drive to the east coast, you would cross the Nullarbor Plain, the world’s largest single exposure of limestone bedrock. It is a long, straight and desolate drive,” says Lacy Gow, a family mediator from Perth. “That being said, there are few reasons to leave Perth if you love sunshine, sand and delicious food and wine.”

The question of remoteness has been explored in Australia perhaps more than anywhere else. During the late 1990s the Australian Commonwealth Government began exploring ways to classify remoteness in order to evaluate service planning, demographic analysis and resource allocation. One of the products that eventually came forth was ARIA+, a system that creates an index, with values ranging from 0 (high accessibility) to 15 (high remoteness), based on road distance measurements from over 12,000 populated localities to the nearest urban areas in five categories based on population size. By this standard, Perth, being a large city filled with services, is a 0.

So if we take a lack of services into account, an attribute generally reserved for smaller cities, then what is the remotest changes yet again. Remoteness becomes less about physical distance from other places than what a city lacks.

Mêdog in south-west China’s Tibet autonomous region. Photograph: Alamy

In the Tibet autonomous region, the valley town of Mêdog, with a population over 10,000, was only connected by road in 2013. While it is slowly changing, the lack of roads or an airport had severely limited the city’s infrastructure, leaving citizens with minimal medical care or education. Reaching the city previously was limited to foot travel and horses, requiring a climb over the more than 4,000 metres above sea level snow-capped mountains Galung La and Doxong La. Still, because of weather, the road is only open just eight or nine months out of the year, not counting closures from frequent mudslides and heavy snowfall.

Yet what is the number of people that actually constitutes a city? There are mining and fishing encampments in Siberia and Patagonia, not to mention uncontacted tribes in the Amazon and Andaman Islands, that are as isolated as any place on earth, yet few would argue that they should be called cities.

The Cambridge English Dictionary defines a city as a large town or any town in the UK that has a cathedral; while erecting a cathedral is no longer a requirement, official city status in the UK can only be declared by royal designation. In the US, the Census Bureau specifies that in order to classify an area as urban rather than rural, it needs a minimum population of 2,500 people, and 1,500 of those people must not be living in institutional housing. Many argue that only a community larger than 100,000 could be called a city, though internationally, there is no official definition.

Regardless of how you measure remoteness, one thing is clear: no matter how large or small the city may be, you are never very far away from the quietude and serenity of the middle of nowhere.

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