We moved through the city like conspirators. Thousands of people stepping quickly through Glasgow destined for one spot. But this was not a football crowd. There were no scarves being waved, songs being sung, or shouts being exchanged. It was all very civilised.

You first noticed it at George Square where instead of people walking in random directions, almost everyone was heading east past the City Chambers. At every street more people joined, turning the streams of people into a human river. There were children, lots of children with parents, but many teenagers and young adults as well. They all knew where they were going even though there were no foam-handed guides showing them the way like there was at the Commonwealth Games. This was Glasgow's annual pilgrimage to Glasgow Green for the fireworks display, 20 minutes of music, noise and colour as 25,000 fireworks burst overhead.

Glasgow's middle-classes can be disdainful about Glasgow Green, seeing it as a gathering place for the coarser elements in society. They don't know what they are missing. Gather in your back gardens with a box of fireworks and mugs of mulled wine as much as you like, but it will never come close to the collective wonderment of the Glasgow Green event - Scotland's biggest fireworks display.

Even the fact that it was held on November the fourth rather than the fifth, didn't deter fans of the whoosh of overhead explosions. In truth one suspects that the council in Glasgow plays down the Guy Fawkes element, the historical reason why there is a fireworks display in the first place. Perhaps they think that celebrating a Catholic plot to blow up a Protestant king being quashed, is not something to be talked up in a city like Glasgow.

So with the fifth also being the night Celtic were playing a European tie at Parkhead, the fireworks were brought forward a day to make it easier to police both events. Not that the fireworks require much policing. It is a free event so there was no need to have folk queuing up at gates to show their tickets, which makes it a remarkably stress-free occasion. There is a fun fair at the Green for early arrivals and mobile caravans of course selling burgers and ice cream. There is never a day too cold to enjoy a cone in Glasgow.

The only admonition for the crowd are signs stating that there should be "No Fireworks. No Alcohol. No Pets." You must have a poor view of the intellect of the average Glaswegian if you think you have to tell them not to bring their dog along to a firework display, but who knows. I did see a group of young girls standing in a circle waving sparklers but there were no Fireworks Police charging through the crowd to stop them. Nor did I see any carry-outs. It's not that sort of occasion.

It also starts on time. The crowd is now over 30,000 - some estimates put it far higher, and we are all vaguely looking over towards the Nelson Monument. There is an area cordoned off there with plastic tubes inside it so that must be the launch pad. There are not hundreds of rows of milk bottles with rockets in them so it is difficult to tell exactly where they will be launched from. Then at seven-thirty the music starts from large speakers dangling from cranes, and the first rocket bursts overhead. Simultaneously fathers of toddlers lift their young ones on to their shoulders. It's the law I think that you have to watch your first firework display from your dad's shoulders.

There are not demented operators picking fireworks out of big boxes and setting them off randomly. Geoff Crow from Edinburgh-based pyrotechnics and events company 21CC explains to me that planning the night started six months ago when the company had its first chat with the council about what the theme would be. It was decided on being upbeat with a space theme. Then with three months to go the music is chosen, fed into a computer, and then broken down to show where the highlights should be so that the bursts overhead coincide with the musical top notes. The company buys most of its effects from China plus some specialist bursts from Mexico and the United States.

"It comes down to experience and knowledge of the product which has been built and tested many times," says Geoff. Computer modelling shows what it will look like before the event. On the night itself, all the effects are controlled by a computer which also controls the music. The fireworks are electronically wired up and the computer sends out the instruction to light them automatically without the need for a human hand with a match. It is all very safe.

"The product is not dangerous. They are largely inert if you don't have a heat source," says Geoff, which basically means if no one is standing around with a lit match beside the fireworks then everyone is safe. And of course safety is one of the reasons the council pays for the display, arguing that having so many people at a controlled event reduces the chances of people burning themselves in their back gardens. Apart from the safety, for me the real reason for the firework display is that winter is a cold, dark, wet, miserable time in Scotland, and without the colourful highlights of first Hallowe-en, then Guy Fawkes Night, followed by Christmas and New Year, we would all be in sloughs of depression.

Meanwhile at Glasgow Green we are all looking skywards as the finale is the Star Wars theme music coupled with loud bursts of colour overheard. In truth I just take Geoff's word for it that the booms and blasts are coinciding with the musical highlights. I'm just marvelling at the spectacle of it all. Shame no one will put me on their shoulders for a better view anymore.