Dressed in turquoise with her trusty black handbag at her side, the Queen smiled and waved to those gathered at the Waverley Station on the day she passes the record set by her great-great-grandmother Queen Victoria to board the new Borders Railway.
The 89-year-old, who is also the nation's oldest ever monarch, has met most of the major figures of recent decades, from India's first Prime Minister Jawaharlal Nehru to Japanese emperor Hirohito.
She will officially become the longest-serving monarch in British history at 1730 (local time) when her reign would have completed 63 years and seven months - calculated at 23,226 days, 16 hours and approximately 30 minutes.
British Prime Minister David Cameron led the tributes to the Queen Elizabeth as he described the 89-year-old ruler as a 'rock of stability' and her service to the nation as 'truly humbling' in an era when so much had changed.
"The reign of Queen Elizabeth has been a golden thread running through three post-war generations, and she's presided over more than two-thirds of our history as a full democracy with everyone being able to vote," Cameron said in the House of Commons, where usual business was postponed for the special tributes.

The Queen paid a personal tribute to her great-great grandmother by wearing a diamond brooch owned by Queen Victoria and passed down to her by Queen Mary.


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