Image source, Various

Of all the tributes being paid to Her Majesty today, perhaps the most unexpected is from Mario - of Nintendo computer game fame - who has given her some exuberant well wishes.

You can hear them, and from the man behind the voice, Charles Martinet, in this clip from BBC Radio 5 live.

Ms Sturgeon, in her earlier speech, greeted the Queen with thanks for her work as the longest-reigning monarch. "We are privileged ma'am that you have chosen to mark today's milestone here," she said. 

"All of us are delighted to be able to share some of this special day with you. For those watching from around the world let me say, on their behalf ma'am, a simple but heartfelt thank you."

Here's footage of the Queen's speech at Tweedbank station, as she marks both the opening of the new railway line, and also mentions her record-breaking day

The Queen has delivered her speech at Tweedbank station - here's footage of her arriving at that stop, which is the end of the new Borders Railway line

The Queen also noted in her speech how many people, including the First Minister Nicola Sturgeon, "have also kindly noted another significance attached to today, although it is not one to which I have ever aspired".

Regarding the celebrations for her record-breaking reign, the Queen also says: "I thank you all, and the many others at home and overseas, for your touching messages of great kindness."

The Queen makes a brief speech at Tweedbank station, unveiling a plaque for the official opening of the new Borders Railway. 

"A long life can pass by many milestones. My own is no exception," she says, of her reign.

Speaking at Tweedbank, First Minister Nicola Sturgeon says the Queen has carried out her duties throughout her reign "with dedication, wisdom and an exemplary sense of public service".

Image source, PA

The BBC's Nicholas Witchell says the crowds at Tweedbank aren't huge but the whole day is being marked in a very low-key way. 

He believes she feels something is not quite right about celebrating passing a record set by her own great-great grandmother - Queen Victoria - but much of the rest of country does want to mark her long reign.

Image source, AFP

It's not just the BBC bringing you the latest news about the Queen today - English town crier Tony Appleton has been proclaiming her record reign outside Buckingham Palace.

Image source, Getty Images

No sign of any tea to go with the biscuits, but here's a shot of a relaxed-looking Queen, Prince Philip and Scottish First Minister Nicola Sturgeon, on the train towards their destination of Tweedbank.

Image source, Reuters

Want to keep up with some of the many images being taken of the Queen's historic day? Then keep an eye on this picture gallery, containing images of Her Majesty and the many tributes being paid to her today.

Image source, AP

After having had the start of her visit delayed, the Queen is now expected at Tweedbank at 13:00 BST.

And here's some footage of the Royal Barge passing beneath London's Tower Bridge, as part of the Thames flotilla marking the Queen's historic day. 

In a BBC interview, her second eldest son, the Duke of York, praises the Queen's consistent leadership over many years. But, he says, that after spending part of the summer holidays with the Queen, she left him in no doubt that she saw today as just a normal working day.

During his Commons tribute, Mr Cameron also paid tribute to Prince Philip who he says has stood beside the Queen throughout her reign. He also says she pioneered the Christmas Day message, opened up the royal palaces and invented the idea of a walkabout. 

His weekly meetings with the Queen are, he says, one of the most enjoyable, inspiring and humbling honours of his office.

Here's Prime Minister David Cameron leading official tributes in parliament to the Queen.

He calls her reign a "golden thread running through three post-war generations".

The PM adds: "She is our queen and we could not be more proud of her. She has served this country with unerring grace, dignity and decency and long may she continue to do so."