The Queen dazzles as she appears to inaugurate the Elizabeth

The Queen dazzles as she appears to inaugurate the Elizabeth Line with Prince Edward

A beaming Queen made a surprise visit to Paddington Station today to see the completed Elizabeth line with her son Prince Edward – days after she canceled her appearance at the State Opening of Parliament due to “mobility issues”.

The 96-year-old, who now rarely makes public engagements outside of her royal residences and carried a walking stick, picked up a limited-edition Elizabeth Line Oyster card. She then topped it up with a £5 note as Crossrail staff showed her how to use the ticket machine.

The monarch wore a sunny yellow double wool crepe coat by Stewart Parvin, which was worn with an A-line silk dress in shades of yellow, royal blue and turquoise and a matching hat by Rachel Trevor-Morgan. She also wore her Singapore brooch.

Her attendance was not publicly announced in advance due to the head of state facing ongoing mobility issues, but organizers were told there was a chance she could attend. She walked slowly around the station concourse.

But in a key note, an hour and a half before Edward’s arrival, Transport for London removed a plaque saying he had opened Crossrail and replaced it with one eight inches lower with the Queen’s name on it.

Following the Queen’s visit, Boris Johnson told the invited guests: “We are all incredibly touched and moved and grateful for Her Majesty for coming to inaugurate the Elizabeth line today. It was fantastic to see her.”

Prince Edward made a return journey from Paddington to Tottenham Court Road. He was asked to stand in the cab during the second leg of the ride. He chatted to driver Carinne Spinola while the train was in motion and told her he was “brilliant”.

After getting off the train at Paddington, the Earl of Wessex said: ‘That was brilliant. I enjoyed that. It was fun.’

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Queen Elizabeth II at Paddington Station in London to mark the completion of London's Crossrail project, which will be known as the Elizabeth Line

Queen Elizabeth II at Paddington Station in London to mark the completion of London’s Crossrail project, which will be known as the Elizabeth Line

The Queen, who now rarely performs public engagements outside of her royal residences and carried a walking stick, picked up a limited edition Elizabeth Line Oyster card before staff showed her how to load it with £5

The Queen, who now rarely performs public engagements outside of her royal residences and carried a walking stick, picked up a limited edition Elizabeth Line Oyster card before staff showed her how to load it with £5

The Queen does not normally carry cash, although she does make an exception on Sundays so she can donate during services

The Queen does not normally carry cash, although she does make an exception on Sundays so she can donate during services

In a key notice, an hour before Edward's arrival, Transport for London removed a plaque saying he had opened Crossrail and replaced it with one eight inches lower with the Queen's name on it

In a key notice, an hour before Edward’s arrival, Transport for London removed a plaque saying he had opened Crossrail and replaced it with one eight inches lower with the Queen’s name on it

The Queen walked slowly as she walked through the concourse with Andy Byford (left), Commissioner of Transport for London, and Prince Edward (right).

The Queen walked slowly as she walked through the concourse with Andy Byford (left), Commissioner of Transport for London, and Prince Edward (right).

The Queen, using a walking stick, smiled warmly as she met workers from Crossrail and Elizabeth

The Queen, using a walking stick, smiled warmly as she met workers from Crossrail and Elizabeth

Dressed in sunshine yellow, the Queen arrived at 11.32am and carefully exited the transparent elevator while holding a walking stick

Dressed in sunshine yellow, the Queen arrived at 11.32am and carefully exited the transparent elevator while holding a walking stick

The Elizabeth Line, named in honor of the Queen (which is pictured today), will open to passengers on May 24

The Elizabeth Line, named in honor of the Queen (which is pictured today), will open to passengers on May 24

The Queen with Edward, Earl of Wessex during the opening of the Elizabeth Line at Paddington Station today

The Queen with Edward, Earl of Wessex during the opening of the Elizabeth Line at Paddington Station today

Prime Minister Boris Johnson with Transport Secretary Grant Shapps and Mayor of London Sadiq Khan travel on the Elizabeth Line today

Prime Minister Boris Johnson with Transport Secretary Grant Shapps and Mayor of London Sadiq Khan travel on the Elizabeth Line today

A Buckingham Palace spokeswoman said: “In a happy development, Her Majesty The Queen is attending today’s event to mark the completion of the Elizabeth Line.

“Her Majesty was aware of the engagement and the organizers were apprised of the possibility that she could attend.”

The Queen gathered for a trip to the Windsor Horse Show on Friday and was the guest of honor at the equestrian extravaganza A Gallop Through History near Windsor on Sunday, the first major event of the centenary celebrations.

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The nation’s longest-serving head of state is just over two weeks away from her celebratory platinum anniversary weekend

Following the Queen's visit, Boris Johnson told the invited guests:

Following the Queen’s visit, Boris Johnson told the invited guests: “We are all incredibly touched and moved and grateful for Her Majesty for coming to inaugurate the Elizabeth line today. It was fantastic to see her.

But today’s engagement is the first outside the Windsor area since she attended the Duke of Edinburgh’s memorial service at Westminster Abbey seven weeks ago.

The Queen and Edward were greeted by Prime Minister Boris Johnson, Mayor of London Sadiq Khan and Transport for London Commissioner Andy Byford.

They met with staff vital to the project who will run the railway, including train drivers, station staff and trainees.

On Sunday, the Queen was the guest of honor at the equestrian extravaganza A Gallop Through History near Windsor, the first major event of the centenary celebrations

On Sunday, the Queen was the guest of honor at the equestrian extravaganza A Gallop Through History near Windsor, the first major event of the centenary celebrations

Transport for London this morning released this new map showing how the first Crossrail services will work from May 24th

Transport for London this morning released this new map showing how the first Crossrail services will work from May 24th

Named in honor of the Queen, the Elizabeth Line will open to passengers on May 24.

Crossrail, the project to build the new east-west railway, was delayed and under budget due to numerous problems, including construction difficulties and complications installing signaling systems.

It was due to be completed in December 2018 and had a £14.8 billion budget in 2010.

The total cost was estimated at £18.9 billion, including £5.1 billion from the government.

The Elizabeth Line will increase capacity and reduce journey times for trips around the capital.

It will stretch from Reading in Berkshire and Heathrow Airport in west London to Shenfield in Essex and Abbey Wood in south-east London.

The trains will initially run in three sections, which are expected to be integrated in the autumn.