Plenty of leading European cities have two or three airports. That includes Paris, Belfast, Moscow and Rome – not forgetting London's half dozen. And that's before you start using Ryanair’s definitions, which means Barcelona has three (Girona and Reus finding themselves embraced within the Catalan capital).

Until Friday, Milan had three airports: Malpensa, 30 miles to the northwest; Orio al Serio, also known as Bergamo, the same distance to the northeast; and Linate, just six miles to the east of the iconic Duomo and well within the city limits.

By taxi the centre of Italy’s financial hub is as little as 10 minutes, while city-break weekenders can take advantage of a local bus to the heart of the city; the fare of €1.50 includes onward transportation by bus, tram or Metro.

Yet Milan’s most convenient airport has closed for the summer peak – and most of the autumn.

“From 27 July to 27 October, Linate will be taking a break for renovation,” the airport announced.

I can’t comment on the state of the runway, though it didn’t seem too bumpy a year ago. I can confirm that Linate’s old and tired terminal certainly needs some care and attention; in the three decades since I first went there, it has simply become increasingly crowded.

Yet an estimated 2.5 million passengers who love Italy’s second city and adore its best airport will be temporarily bereft.

It is standard practice among smaller Italian airports to close completely for runway repairs. Flights are diverted to nearby airports for a couple of weeks. But no previous closure has involved so important a gateway, nor continued for so long.

If all the passengers who normally use Linate went to Malpensa instead, it would represent a 45 per cent increase in passenger numbers at “MXP” – already under pressure as the main international airport for Milan.

Yet by no means all of the current users of Linate will head for the big, tricky-to-reach gateway.

Plenty of regular Linate travellers really should know better: they simply head for Linate in order to hop to Rome Fiumicino on the Alitalia shuttle. Between 7am and 9am on a Monday, for example, there are no fewer than 10 flights heading south to the capital.

Yet Milan to Rome is also the nation’s principle high-speed rail link, with trains now taking less than three hours between the two main cities.

When a key transport link shuts down temporarily, the evidence is that a proportion of users never returns. Which is bad news for Alitalia – which has by far the largest share of slots at Linate, due to some questionable allocation of these precious assets over the years.

I imagine that the Italian national carrier, which has chronic financial problems, will suffer long beyond the temporary closure of the link. Once business travellers discover how fast and stress-free the rail connection is, demand for those hyper-frequent flights is likely to dwindle.

Which could spell good news for British Airways and easyJet, and those of us who fly on them. They would love to have more services to Linate – and other airlines might move in to link Manchester or Edinburgh to the close-in airport.

Bergamo could blossom, too: British Airways is adding a service from Gatwick to Orio al Serio airport, which will cheer up prospective visitors who, for whatever reason, do not wish to use Ryanair.