The information is among 60 facts released by Buckingham Palace to celebrate their diamond anniversary.

Another fact reveals how their wedding cake on 20 November 1947 was 9ft (2.74m) high.

Royal family members will attend an event hosted by Prince Charles later at Clarence House to toast the milestone.

The Queen is the first British monarch to celebrate a diamond wedding anniversary.

The list of wedding facts also disclosed that on the day of the wedding, the grave of the Unknown Warrior was the only stone not covered by a special carpet inside Westminster Abbey.

The day after the ceremony, the Queen followed a tradition started by her mother of having her wedding bouquet returned to the Abbey to be laid on the tombstone.