In pictures: Elizabeth II becomes longest-reigning monarch

The Queen has been continuing her official duties in Scotland on the day that she becomes Britain's longest-reigning monarch.

The Queen has reigned for 63 years and seven months - calculated at 23,226 days, 16 hours and approximately 30 minutes from 17:30 BST

Elizabeth II passed the record set by her great-great-grandmother Queen Victoria. This is one of the official pictures released by Buckingham Palace to mark her 63-year reign

Crowds greeted the Queen and the Duke of Edinburgh as they arrived at Waverley Station in the Scottish capital

Before their arrival onlookers applauded the performance of the National Youth Pipe Band of Scotland which marched through the station

The royal couple then spent a few minutes meeting and chatting with the crowd

The Queen boarded a steam-hauled train with Scottish First Minister Nicola Sturgeon on her way to formally open Scotland's new £294m Borders Railway

While on board the monarch made an effort to wave to fans as they lined the tracks of her route

Before arriving at Tweedbank the Queen stopped off at Newtongrange in Midlothian to unveil a plaque to mark the opening of the station

And once again she was met by cheering fans

Well-wishers also gathered at Tweedbank to wave flags in anticipation of her arrival

Her jewellery for the day's events was specially chosen in recognition of her great-great grandmother Queen Victoria, whose reign she has overtaken. Her bow brooch used to belong to Victoria

In London, people have been heading to Buckingham Palace to look at a photographic exhibition of the Queen, entitled Long to Reign Over Us

As part of the celebrations the BT Tower flashed the message "Long may she reign"

Also in the capital, a flotilla of historic vessels sailed along the Thames to mark the Queen's special day

The procession started from Tower Bridge, and ended at the Houses of Parliament

Onlookers also lined Westminster Bridge to see the flotilla pass by

Memorabilia to mark the occasion is also being sold at the Buckingham Palace shop