As the Queen and Prince Philip approach their seventieth wedding anniversary, Kirsty Young offers a unique view of their life together. It is a love affair that is said to have started with the briefest of encounters on a rainy day in July 1939, and one that was sealed with a fairy-tale wedding on 20 November 1947. In the decades that followed, the couple have experienced the same milestones as many others - with the birth of children, grandchildren and many more moments of pride, but they have also had to survive challenges few others have had to face. Every step of their life together has been played out in public, but through it all, the Queen and her prince have not only kept their relationship strong, they have kept the nation strong too, steering it through decades of change. Kirsty looks back at their remarkable seven decades together to celebrate the longest royal marriage in British history.