Will the birthday of an 80-year-old grandmother prove a bigger attraction than the civil partnership ceremony of Sir Elton and David on this spot? And will it outshine the more conventional marriage of Charles and Camilla in the same building? Both drew the curious in considerable numbers.

It did not, at that early hour, look promising. Castle Hill was starting to fill up but the crowd barriers placed in hope all down the quarter-mile High Street still stood forlorn, with no one to restrain.

In the event, the grandmother won the day comfortably. By the time she emerged from the castle’s great oak doors at noon, an estimated 22,000 loyal subjects — and a fair number from lesser nations, such as the United States — packed the centre of Windsor to bursting to cheer the Queen on her extended birthday walkabout.

They stood six deep the entire length of her route and crammed every upstairs window. A couple dressed as Elizabethans of the Tudor variety stood on the roof of the Edinburgh Woollen Mill opposite the castle gate and, oblivious of the historical anachronism, loyally waved Union Jacks.

The crowd was high-spirited and brimming with that mixture of love and respect that we bestow on our honoured elders. Police reported two arrests for minor public order offences. The same, however, could not be said of the behaviour of the dogs.

Jennifer Hawkins, from Worthing, West Sussex, had arrived early to claim a prime spot opposite the castle gate, accompanied by an inflatable plastic joke-shop corgi that she tethered to the barrier. Along came a police officer with his sniffer spaniel, checking the crowd for explosives. The spaniel did not like the corgi one bit; it had not encountered its like in an entire police career. So it savaged the corgi’s ear, leaving it in tatters; miraculously, the corgi did not deflate.

At the top of Castle Hill the band of the Irish Guards was warming up with a stirring march. Alfie, the wire-haired German pointer, another member of the Thames Valley force, decided that he did not care for the tune and barked his head off, drowning out not only the band but also the aircraft that droned overhead every 90 seconds.

On a kind April day with the sun almost breaking through, the specially big Royal Standard that is flown on significant occasions drooped lazily above the castle’s Round Tower in the warm, still air. The emergence of the Queen through the castle gates loosed a burst of cheering and applause, a rendition of Happy Birthday to You by the band and another discussion.

How to describe the colour of her coat and matching Philip Somerville hat? We aired cherry red, we toyed with fuchsia but, after consulting several women, who are better at these things, we settled for cerise. On one thing all were agreed: you wouldn’t miss it in a crowd.

Accompanied by the Duke of Edinburgh in a subfusc fawn raincoat, the Queen accepted birthday cards from a line-up of children representing the Boys’ and Girls’ Brigades, the Scouts and St John Ambulance, to all of whom she has been patron throughout her reign. A young Guide and a Brownie gave her a teddy bear.

Then, as the band slipped into some nicely syncopated jazz, she moved to a class from St George’s School, Windsor, who gave her a large floppy paper card in the shape of a cut-out Queen. It is one of the great advantages of a Windsor education: you are constantly able to bunk off lessons and pad out a royal crowd.

For the next 45 minutes the Queen moved slowly along the street, constantly crossing from one side to the other and everywhere enjoying the warm breeze of adulation. She was presented with so many cards and bouquets that 20 army and RAF cadets had to form a human chain to take them from her.

Children chanted: “Two, four, six, eight, who do we appreciate? Oh, Oh, Oh, the Queen.”

Police officers on duty sneaked tiny digital cameras from their pockets and snatched commemorative snapshots. Sir Robin Janvrin, the Queen’s private secretary, walking a few steps behind her, beamed like the cat that got the cream. The size of the crowd had thoroughly dispelled any damp-squib fears that he may have harboured.

After 30 minutes the Queen reached the Guildhall, where her burgundy Bentley was parked with engine running lest she sought escape; but she pressed on for another quarter-hour all the way down the high street to constant cheering, whistling and applause.

Outside the Church of St John the Baptist, the vicar, the Rev Mary Barnes, proffered a large birthday cake, enough for 300 slices and decorated with the figure 80. The Queen ceremoniously cut it, declining to blow out the candles. Another wellwisher gave her a hideous Union Jack baseball cap that she held up to her husband, her face clearly reading: “I think this would look better on you.”

Eric Wiles, the Mayor of the Royal Borough of Windsor and Maidenhead, had plans to read a loyal address, but settled instead for a loyal birthday card. “I think she was a little bit overwhelmed by the size of the crowd and its spontaneity,” Mr Wiles said from within his scarlet and ermine.

We were assured by him that Windsor’s battery of municipal artillery had fired a 21-gun salute in Home Park. Just as well that Alfie the German pointer was out of earshot. At 12.45pm the Queen climbed into her car and returned to the castle for a private lunch and an afternoon with her feet up before a black-tie dinner hosted by the Prince of Wales at Kew Palace last night.

A police marksman on the castle roof put down his binoculars and gun and climbed back to earth. He was the only man in Windsor who had had a quiet day.

www.timesonline.co.uk/pictures

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