How the mail travels across the world

The postal services of the world combine to make a planet-sized brain of stupendous complexity. Most of the world’s 4000 million people could if they wished communicate with almost anyone else by post within a few days.

The quantity of mail handled by the world’s 654,000 post offices is staggering. On any one day, almost 1000 million items pass through the international postal system.

To shift a letter physically (rather than communicating its contents electronically) is a slow-motion, labour-intensive operation that is a constant challenge to the millions who work for the 169 member-states of the World Postal Union.

From Peace River to Nice

Every item posted becomes part of this epic business. Imagine, for instance, that Pierre, a young French engineer newly assigned to Peace River, Alberta, in Canada, writes a letter to his grandmother who lives near Nice in the south of France.

In Peace River, a town of about 6300 people at the head of a broad valley rich in oil and natural gas, Pierre posts his letter on Monday morning, giving news of his safe arrival to do geological research.

After collection that afternoon, the letter joins a few thousand others in the local post office. The postal workers separate the local mail from letters going to other parts of Canada. They also sort international letters into two bundles, one for shipment west across the Pacific, the other for all points east, including Europe. By evening the bundles, minus Peace River’s local mail, are travelling by truck 100 miles (160km) south-west to the larger town of Grande Prairie.

Here, the two international bundles join other similar bundles from nearby towns.

Next morning, Tuesday, a second truck-ride carries the mail 300 miles (480km) south-east to the provincial capital, Edmonton. The size of the two international consignments increases again, before they are taken from Edmonton post office to the airport.

At this point, the two batches go separate ways – the transpacific bags flying west to Vancouver and the others east to Toronto, where they arrive late on Tuesday.

In Toronto, the letters are sorted by country, and in some cases by area within a country. The process takes most of Wednesday and Thursday, and Pierre’s letter joins the 7301b (330kg) pile of mail destined for France.

On Thursday evening, an international flight leaves Toronto carrying the letter to Charles de Gaulle Airport in Paris, where it arrives early on Friday morning. The letter is now on the fifth day of its journey.

Letters from Canada are dispatched from the airport to Paris, where they merge with the 50 million objects handled daily by the country’s highly mechanised system. The postcode for Pierre’s grandmother’s house is read by a coding machine which adds a bar code indicating where the letter will finally be distributed from. The machine deals with 40,000 letters an hour.

A second machine sorts the letters into bundles corresponding to the departements – the French equivalent of counties or states. A conveyor belt carries them from the machine to bags, which are carried by more conveyor belts to the trucks and trains which, along with planes, fan out across the country with their daily 3000 tons of mail. The post office uses an Airbus to carry mail to Marseilles and Nice, and Pierre’s letter is aboard the Friday afternoon flight.

Overnight in Nice, the same collecting and sorting operation is carried out, but in reverse. The sorting depot divides the mail into sub-zones for local distribution. Early on Saturday morning, a van carries the mail from the sorting depot to the post office.

The post office puts Pierre’s letter into one of the nation’s 70,000 postal rounds, and his grandmother reads his news over her morning coffee on the sixth day of its journey from Peace River.

That, at least, is how it would work in an ideal world. Inevitably, there are complications. Like weekends and holidays. And ton upon ton of ungainly parcels and illegible envelopes. And strikes. And breakdowns. And Christmas rushes. Though such factors often combine to force delays, every delivery is a minor tribute to human ingenuity and cooperation.