She could be any grandmother setting off to see the family at Christmas - although the bunch of flowers she is clutching is a giveaway.

The Queen today shunned the expense of the royal train or a chauffeur and took the 10:45 from King's Cross to King's Lynn, in Norfolk, along with hundreds of other travellers, before continuing her journey on to Sandringham.

Look who I saw down the station: A fellow passenger snaps Her Majesty as she boards a First Capital Connect train at King's Cross Station bound for King's Lynn, Norfolk, en route to Sandringham for Christmas

There was a buzz at King’s Cross this morning as platform 11b began crawling with police.

Could it be a drug bust, the crowd wondered? Or was a rock star about to board a train?

Then a small lady in a headscarf appeared, a handbag on one arm and a posy on the other.

Fellow passengers on the 10.45 First Capital Connect service to King’s Lynn couldn’t quite believe their eyes as the Queen stepped on board a first class carriage.

Her Majesty paid £44.40 for a single first class ticket and sat in a reserved carriage with her protection officers.

The Duke of Edinburgh is already at Sandringham.