Dailysighted...: 'Long May She Reign', Queen Elizabeth is business as usual as she arrives to open Scottish Borders Railway

The Queen surpasses her great-great grandmother Queen Victoria to become Britain's longest reigning monarch
Rather than mark the milestone with celebratory events, Her Majesty will carry out official duties in Scotland
The monarch will be joined by the Duke of Edinburgh as she opens the new £294million Scottish Borders Railway

Waving at crowds of gathered well-wishers, the Queen looked relaxed as she arrived at Edinburgh's Waverley Station this morning.

The Queen today surpasses the record set by her great-great-grandmother Queen Victoria to become Britain's longest-reigning monarch. But rather than mark the milestone with high-profile celebrations, it will be business as usual for Her Majesty as she carries out official duties in Scotland.

The Queen was accompanied by Prince Philip as she met First Minister Nicola Sturgeon at the station. The party boarded a steam train to the village of Tweedbank, where she will open the new £294million Scottish Borders Railway.

The monarch's wish to make the day as normal as possible did not stop hundreds of well-wishers from gathering outside, clutching Union flags and in a show of support. Her arrival was met with a huge cheer, as a pipe band played to mark the occasion.

Welcome: The Queen appeared in good spirits as she received a bouquet from a young girl on her arrival at Waverley Station, in Edinburgh

Applause: Crowds cheered as the monarch stepped out of her car at Waverley Station, where she was greeted by Nicola Sturgeon

Celebration: One-year-old Ashford Gardiner, centre, from Galashiels, is among those waiting at Tweedbank to greet the Queen later today

On the move: The Queen was accompanied on her journey by the Duke of Edinburgh and Nicola Sturgeon, pictured seated at a table

The exact moment the Queen eclipses Queen Victoria's milestone is not known as there is no precise time for the death of the Queen's beloved father, George VI, who died in the early hours of February 6 1952.

But Buckingham Palace has calculated that at around 5.30pm the Queen will make history as she will have reigned for 23,226 days, 16 hours and roughly 30 minutes - a few minutes longer than Queen Victoria.

Steam billowed out of the train as it pulled away from the Edinburgh station. Inside, the Queen could be sitting next to Nicola Sturgeon at a linen-covered table. Her husband the Duke of Edinburgh was sat opposite.

The party are making their way to the village of Tweedbank, where the official opening ceremony for the Scottish Borders Railway will take place. They are taking the same route as the new rail service, stopping in Newtongrange, Midlothian on the way.

At Newtongrange, hundreds of people who had gathered in the area around the small station cheered as the Queen and Duke stepped from the train.

The royal couple spent a few minutes chatting to well-wishers, many of them schoolchildren, before the Queen unveiled a plaque to mark the opening of the new station.

For the last leg of the journey to Tweedbank, the Queen, Prince Philip and the First Minister were joined by individuals who had a connection with the area's railway.

There, the Queen is expected to deliver a speech but it is thought the focus will remain on the railway, with only an oblique reference to the significance of the occasion. She will later return to Balmoral Castle in Aberdeenshire, where she is currently spending her summer holiday.

Meanwhile, Prime Minister David Cameron led MPs in paying tribute to the Queen in Parliament today. Mr Cameron said it was 'truly humbling' to comprehend the scale of the Queen's public service, comparing her reign to a 'golden thread running through three post-war generations'.

Setting off: Waving to her loyal subjects, the Queen is seen looking out the window as the train leaves Waverley Station

Official duties: The Queen, who was seated at a table next to Nicola Sturgeon, leaned forward to look at those supporting her at the station

Reflection: The Queen, who was seated across the table from the Duke of Edinburgh, appeared deep in thought as the train pulled away

Guest: First Minister Nicola Sturgeon, pictured greeting the Queen on the platform, is among those making the rail journey with the Queen

Mr Cameron prompted laughter in the Commons when he said: 'Whether it's something we suspect she enjoys, like the Highland Games, or something we suspect she might be slightly less keen on, such as spending new year's eve in the Millennium Dome, she never, ever falters.

'Her selfless sense of service and duty have earned her unparalleled respect and admiration not only in Britain but around the world.'

The Prime Minister announced earlier that the Cabinet have given the Queen a leather-bound copy of Cabinet papers from October 1952, shortly before her first opening of parliament.

Acting Labour leader Harriet Harman also paid tribute to the Queen in the Commons, saying there can be 'no doubt of the commitment that she has made and the public service she has given, and continues to give.'

Tower Bridge was lifted in tribute to the Queen as the royal rowbarge Gloriana led a flotilla of boats down the River Thames in her honour

As the procession passed HMS Belfast, a four-gun salute sounded out and the Massey Shaw fireboat shot jets of water across the Thames

She added: 'Her life has been a great sweep of British history - the Second World War, the Cold War, the fall of the Berlin Wall, and she's presided over the transition from empire to Commonwealth.

'It's entirely characteristic of her that she has let it be known that she doesn't want there to be a fuss about today, but we are making a fuss and deservedly so.'

The bells of Westminster Abbey, where the Queen was married and crowned, also sounded out in tribute to the monarch. Bell-ringers rang a quarter peal for 50 minutes. The then Princess Elizabeth wed the Duke of Edinburgh at the Abbey in 1947, and was crowned there less than six years later.

Meanwhile, Tower Bridge was lifted in tribute to the Queen as the royal rowbarge Gloriana led a flotilla of boats down the River Thames in her honour. The vessels set off east from the bridge at midday, sounding their horns for one minute in recognition of her service.

Dress up: Children from Busy Bees Nursery wait at Tweedbank station ahead of the arrival of Queen Elizabeth II and the Duke of Edinburgh

Princesses for a day: Hannah Walton, five, right, is one of a number of young girls waiting to greet the Queen at Tweedbank

Excitement: The Queen is expected to deliver a short speech when she arrives at Tweedbank, where crowds have already gathered

As the procession passed HMS Belfast, a four-gun salute sounded out and the Massey Shaw fireboat shot jets of water across the famous waterway. Smartly dressed Naval officers lined up up aboard HMS Portland, next to HMS Belfast, to salute the flotilla.

Among the boats was the Havengore, which was used to transport Sir Winston Churchill's body on the day of his state funeral in 1965, as well as the steam ship SS George Stephenson. Throughout the day, the message 'Long May She Reign' is being scrolled across the BT Tower in central London.

At St George's Chapel at Windsor Castle, the monarch's favourite residence, prayers are being said to mark the historic day. Meanwhile, Buckingham Palace, Edinburgh's Palace of Holyroodhouse and Windsor Castle have unveiled special outdoor exhibitions of photos.

Long To Reign Over Us, which can be viewed by visitors to the palaces and castle, includes official portraits and images of the Queen from 1952 to the present day, such as Cecil Beaton's 1953 official Coronation Day portrait, as well as informal pictures of the monarch and her family.

A pipe band paraded through the station as the Queen arrived. She was greeted by Nicola Sturgeon before boarding the train

Celebration: A man shows his support in a jacket and hat printed with the Union flag. Right, a young girl wears tartan outside the station

Tour: First Minister Nicola Sturgeon took a look inside the cab of the steam train, Union of South Africa, before the journey

Royal welcome: Well-wishers outside the train station, where the Queen and the Duke of Edinburgh arrived this morning

In Windsor, a special walking route named The Queen's Walkway has been completed by the Outdoor Trust. The Walkway connects 63 points of interest such as the Henry VIII Gateway of the Castle and the Guildhall where the Prince of Wales married the Duchess of Cornwall in 2005.

It stretches for 6.37km to symbolically represent the 63 years and 7 months the Queen has reigned.

Sir John Major, one of the 12 prime ministers of Elizabeth II's reign so far, is among the high-profile figures who have paid tribute to the Queen today.

Describing the sovereign as an 'absolute constant' in British life, Sir John told BBC Radio 4's Today Programme: 'Throughout the last 60 or so years, the Queen has been an absolute constant.

'LONG TO REIGN OVER US': 1ST CLASS STAMPS TURN PURPLE TO MARK QUEEN'S RECORD-BREAKING REIGN

Change in colour: The red 1st class stamp has been turned purple

The 1st class stamp is turning purple to mark the Queen's historic record-breaking reign.
The 63p stamp, which features the monarch's profile by sculptor Arnold Machin, has switched from its regular red to regal purple for the next 12 months in celebration.
Its iridescent overprint, which usually reads 'Royal Mail', now bears the text 'Long to Reign Over Us', Royal Mail revealed.
It is the first time the colour purple has ever been used for what is known as the First Class Definitive stamp.
Andrew Hammond, stamps and collectibles director at Royal Mail, said: 'Royal Mail stamps mark the most significant anniversaries and landmark events in the life of our country.
'We are proud to commemorate Her Majesty becoming the longest-reigning monarch in UK history.'
The new stamp, along with a collection of four others, has been issued on the day the Queen becomes Britain's longest reigning monarch.
The miniature sheet of stamps includes a 1st class stamp featuring William Wyon's City Medal head of Queen Victoria - the country's previous longest reigning monarch.
The image on the Penny Black - the world's first postage stamp - was based on this portrait, which came from a sketch of Victoria when she was 15 years old.
Another 1st class stamp features Dorothy Wilding's three-quarter profile photograph of Elizabeth II which was printed on British postage stamps from 1952 until 1967.
There are also two £1.52 stamps. The first shows the Badge of the House of Windsor with the Castle's Round Tower of Windsor Castle flying the Royal Standard.
The second features the Queen's Personal Flag, designed in 1960 for use in Commonwealth countries.
It includes an 'E' with a crown, surrounded by a garland of roses.

The new stamp, along with a collection of four others, has been issued on the day the Queen becomes Britain's longest reigning monarch

Mark of respect: The message 'Long May She Reign' scrolled across the top of the iconic BT tower in central London this morning

Even the lemurs at Drusillas Park, East Sussex, joined in the celebrations, holding Union flags in their enclosures

Official duties: The Queen and the Duke of Edinburgh will board this steam train with Scottish First Minister Nicola Sturgeon

The royal party will travel the new route, stopping off at Newtongrange in Midlothian before carrying on to the final station on the railway

'Whilst prime ministers have come and gone, celebrities have come and gone, life has changed, she and the monarchy have been an absolute constant in their lives and I think that is very reassuring.'

Meanwhile in London, the Duchess of Cornwall described the Queen's reign as 'unbelievable' when she appeared on ITV's This Morning. The Duchess was on hand to help the broadcaster mark it's 60th anniversary.

Speaking to ITV News' Alastair Stewart, the Duchess of Cornwall said: 'I just can't believe it's as long as Queen Victoria...such a big person in history, you know, to beat that and you know, with such style.'