The Glasgow Subway. It's adorable. Round and round she goes, underground she goes.

One of my favourite visual gags is when a novice comic overlays Scotland's underground railway map with those of Paris, New York and London.

The complex spider webs and snowflake weaves of the big cities and then Glasgow's no-nonsense oval simplicity pat on top. Snort.

But while the subway sits with dear affection in the city's heart, when does its simplicity become a metaphor for a wider lack of transport ambition?

Two things have been trumpeted this week: one, the transit system's extended Christmas opening hours. I almost wish SPT wouldn't keep up this annual tradition. One becomes used to improved operating times and then has to readjust to the decrease once the tinsel comes down.

It makes the standard limited weekend travel times harder to swallow.

A second - the new trains have arrived! I first wrote about these new subway carriages when they were delivered in 2019. It was hailed a "fantastic day for the subway" by councillor Martin Bartos, who was then-SPT chairman.

To be fair to SPT, the transport partnership did signal that the testing programme from Stadler, the manufacturer, would be intensive and lengthy. And no one knew a pandemic would interrupt proceedings.

So here we are, four years later, and the first two trains rolled on to the tracks this week. They form the latest step in a subway modernisation process that began in July 2011 and, when finally completed, it will be time to start again.

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I jest but Glasgow's subway and modernisation are only sporadic bedfellows. In a glorious clip from 1975, Blue Peter's Peter Purvis, wearing spiffy flares, boards a subway carriage and explains to the presumably agog young viewers: "Trains first ran in 1896. There's been hardly any modernisation. Except the price of a ticket".

Plus ça change, Peter. Plus ça change.

In the clip, Mr Purvis hands his ticket to a conductor who, he explains, is wearing a uniform that hasn't been updated in 74 years. It is so outdated, this uniform, that it still has black braid to signify a nation in mourning. Mourning who?

Queen Victoria, who died in 1901. Of course, changes have been made in the interim but in its 127 years these renovations stretch only to cosmetic improvements and upgraded technology.

In 2016 I had the privilege - and it genuinely was fascinating - of going down into the subway tunnels overnight to see the modernisation works taking place first hand. We went round the tracks on a "loco"- a battery operated cargo train - that had no roof or solid sides.

The Herald:

It felt a little like being in a black and white movie where the baddies are making off on a pump handcart.

The engineers explained to me at the time that a lot of what they were doing was incredibly similar to techniques that would have been used by their Victorian forebears 100 years prior. Due to the unusual dimensions of the subway the equipment used for heavy rail isn't suitable so pulleys and rollers are used instead.

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Glasgow's, famously, is the third oldest underground in the world but has never been extended beyond it's original cute loop. As an aside, talk of the subway circle always puts me in mind of when UKIP called for London's Circle Line to be "a circle again" in their 2010 manifesto. There's nothing like a snappy pledge: Stop the Boats, Make America Great Again, Return the Circle line to a circle.

Anyway, the great Glasgow subway is a pointless piece of infrastructure to the vast majority who live in the city. Because so few people have access to it, it's underused for a city of Glasgow's size.

If you compare us to, say, Lisbon, a geographically smaller and less populated city where the annual underground ridership is 140.9 million, our annual ridership is 12.8m, despite having the larger population.

A niche treat for a select few, which is a great pity because it is the best way to get around. It's by far the best for frequency of service at peak times, it's never snarled up in traffic, it's relatively well priced and it runs in all weathers.

When I'm living in the west end, as I do for a few months of the year, it is honestly transformative to know that I can run out of the flat, hop on the subway and be where I need to be quickly without the rigidity of train times or waiting for buses that don't turn up. If only everyone had access to this.

The placement of some subway stops seems rather haphazard now but this is due to the changing nature of housing in the city. Kinning Park, Shields Road and West Street used to have sufficient property density to be sensible places for metro stations.

But tenements were demolished to make way for the M8 and M74 - now also in a bad state of repair in places. These stations are surrounded by brownfield sites.

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If we look at the subway's accessiblity as an urban planning problem then it makes sense to push for housing on these sites that will be immediately connected to Glasgow's best transport link.

The dream would be to extend the subway, as other countries have successfully managed.

Support for extending the subway is not limited to fringe groups. In 2007 SPT produced a report that showed residents of Glasgow to be greatly in support of extending the subway and said it was "in tune with the needs of the public".

Councillor Alistair Watson, of the SPT board, is quoted as saying: "I realise an extension won’t come cheap and we still have lots of hurdles to overcome but, in my view, what the public wants, the public should get."

Labour, riding high from the successful Commonwealth Games bid, promised the subway would be extended in time for Glasgow 2014.

The then-SPT chairman Alistair Watson said: “We will deliver the East End extension for 2014. I am being unequivocal about that.” He also promised the Glasgow Airport Rail Link.

Of course, that was pre-financial crash and the entirely of Britain was a PFI construction site. But in 2017 the SNP said it would plan to extend the subway if it won the council election.

Councillor Kenny McLean said: “We will look at possible extension of the Subway and consider innovative funding methods, such as City Bonds, to fund this work."

The party's first move, he added, would be to take the subway out of SPT control. It never happened.

The new subway carriages are very nice and very bright but they are small beer compared to what other cities achieve. In the time gums have been bumped about this, Transport for London has completed the new Elizabeth line - for better or worse - to extend the capital's rail network by 73 miles.

Copenhagen has opened its M3 City Circle Line, the Cityringen, with 17 new underground stations added to the city’s transport system. A fourth metro line is being constructed now.

Extending Glasgow's underground system is periodically breathlessly pledged but never in any truly meaningful way. Any political desire to extend the subway is usurped now the idea of the Clyde Metro has been mooted - the plan to finally create a mass transit system for Glasgow, which is being led by SPT.

SPT is currently working on a strategic business case for the Metro and who knows how long it will take for the plans to become reality. Given how relentlessly Glasgow is chopped and changed and disappointed by public transport planning it's maybe best not to be too excited just yet.

In the meantime, if you have the chance, enjoy the shiny new subway trains. They're the biggest improvement we can expect. Round and round we go.