Scottish National Party leader Nicola Sturgeon has paid tribute to the Queen during the inauguration of the new £294 million Scottish Borders Railway.
Ms Sturgeon said the Queen's reception showed the "strong admiration and affection" felt for her in Scotland.
"You have carried out your duties with dedication, wisdom and an exemplary sense of public service," she said.
"You are admired and held with great affection and esteem in the UK, across the Commonwealth and around the world."
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Fashion and portrait photographer David Bailey said the Queen has the most recognisable face in the world and a "twinkle in her eye".