The Queen stunned regulars at a traditional Scottish pub when she popped in for a slap-up meal and a tipple.

Britain's longest serving monarch made a secret visit to the oldest bar in the country during her stay at Holyrood Palace in Edinburgh last Friday.

And she only gave workers at The Sheep Heid Inn an hour to prepare for the Royal visit.

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The 90-year-old had spent the day at Musselburgh Racecourse before taking a window seat in the pubs' dining area.

Her party are understood to have ordered a martini and a half bottle of white wine, along with two portions of lamb and a fillet of seabass.

The main meals are advertised at £16.50 each on the pub's regular menu but it is not known which of the meals the Queen ordered.

Staff at the pub have been sworn to secrecy but were able to confirm that the head of state visited.

A worker said: "I've been sworn to secrecy unfortunately and have no idea how her visit got out there."

The Herald:

Regular customer and Edinburgh City councillor Alex Lunn said: "The Sheep Heid Inn is something the local community are very proud of and a visit from the Queen is another string to add to its bow.

"I eat there regularly so I'm sure Her Majesty enjoyed an excellent meal."

The Sheep Heid Inn which was established in 1360 has been linked to the Royal family since the 1500s.

One story of how the pub got its name states that in 1580, King James VI of Scotland gifted the landlord an ornate ram's head snuff box.

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It is believed he and his mother, Mary Queen of Scots, stopped by the inn many times to play skittles in the courtyard.

As a mark of gratitude, he presented the landlord with the unusual gift which remained on site for 300 years before being sold at auction to the Earl of Rosebery.

It is very rare for The Queen to dine out in public, other than at private London clubs and hotels.

The exclusive Bellamy's restaurant in Mayfair is believed to be the only restaurant she has eaten at in London, and only on a few occasions with her family.

Earlier in the day, the Queen wore a royal blue suit and hat while she attended Musselburgh Racecourse to celebrate its 200th birthday.

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She was accompanied by the Duke of Edinburgh and is understood to have watched the action from inside the racecourse's VIP hospitality areas.

The Queen did not appear to have had time for a quick game in the pub's historic Skittle Alley before making the short journey back to the palace.

Robert Louis Stevenson, Robert Burns and Bonnie Prince Charlie - as his army was encamped at Duddingston for a month prior to the Battle of Prestonpans - are among the inn's other famous patrons.

Last year, US pop star Kelly Clarkson also visited the pub, enjoying a beer and "chunky chips" in peace as the majority of locals failed to recognise her.

Buckingham Palace declined to comment on the Queen's visit to the Sheep Heid Inn, other than to say that she had spent the evening "privately".