The Queen has made a surprise appearance at the official opening of the Elizabeth Line, the London Crossrail project named in her honour.
The 96-year-old monarch arrived at Paddington Station alongside her son, the Earl of Wessex, to mark the completion of the line.
It is the Queen’s third public appearance in just five days after delighting onlookers with visits to the Royal Windsor Horse Show on both Friday and Sunday evening.
The Queen was not scheduled to attend the Crossrail event but is understood to have been keen to be there and felt well enough this morning to join Prince Edward.
Her jolly demeanour in recent days has buoyed spirits ahead of the Platinum Jubilee weekend, raising hopes that she will be well enough to attend at least some of the celebrations during the four-day bank holiday weekend.
Ill health has forced her to pull out of a string of high profile engagements in recent months, including last week’s State Opening of Parliament.
Buckingham Palace said she had been suffering from “episodic mobility problems.”
Queen buys first Crossrail ticket
The first indication that the Queen would put in a surprise appearance at the Crossrail event came an hour and a quarter before the Earl was due to arrive, when Transport for London removed the plaque that he had been due to unveil stating that he had opened the line.
It was replaced by one saying it had been opened by the Queen. The height of the plaque was also lowered by eight inches to take account of the fact that the Queen is shorter than her son.
A Buckingham Palace spokesperson said: "In a happy development Her Majesty the Queen will attend today's event to mark the completion of the Elizabeth Line. Her Majesty was aware of the engagement and the organisers of the possibility she may attend."
The Queen was due to buy the first ticket, using a commemorative Oyster card topped up with £5.
However she passed up the opportunity to travel on one of the new trains, instead returning to Buckingham Palace while Edward was given the privilege of becoming the first passenger, travelling to Tottenham Court Road and back.
It was the third line opened in London during the Queen's reign named in honour of the royal family.
When she opened the Victoria Line in 1969 she had to put a coin in a machine to get her ticket, and travelled in the driver’s cab. The Jubilee Line was named after her Silver Jubilee, but did not open until two years later.
The Queen and the Earl met staff who have been key to the Crossrail project, as well as Elizabeth Line staff who will be running the railway, including apprentices, drivers, and station staff.
On arrival, they were welcomed by Boris Johnson, the Prime Minister, Sadiq Khan, the Mayor of London and Grant Shapps, the Secretary of State for Transport.