1. The Earl of Wessex’s initials spell out 'EARL' – Edward Antony Richard Louis.

2. HRH wrote and narrated two films about The Duke of Edinburgh’s Award shown on BBC television in April 1987, and was involved in an earlier series made by TV-am.

3. The Countess has five military appointments: Royal Colonel of the 5th Battalion of The Rifles (UK); Sponsor of HMS Daring (UK); Colonel in Chief of Queen Alexandra's Royal Army Nursing Corps (UK); Colonel in Chief of the Lincoln and Welland Regiment (Canada); and Colonel in Chief of the South Alberta Light Horse Regiment (Canada).

4. The last person known as 'Earl of Wessex' was Harold Godwinson, prior to his accession to the English throne as King Harold II in 1066.

5. The Earl has two honorary degrees from Canadian universities: from the University of Victoria, awarded in August 1994, and from the University of Prince Edward Island, awarded in October 2007.

6. The Countess is patron of Girlguiding UK, the UK's largest all-female organisation.

7. While at university The Earl learnt to play Real Tennis, and continues to play today. He is Patron of the International Real Tennis Professionals Association and Patron of the Tennis and Rackets Association.

8. The Countess became the first Patron of ChildLine on 20 April 2005.

9. In keeping with the tradition of using Welsh gold for Royal wedding rings, the gold for the wedding rings of The Earl and Countess came from The Prince Edward mine in Trawnsfynydd, Gwynedd, North Wales. Previous Royal wedding rings were made of gold from the Clogau St David’s mine in Bontddu, North Wales.

10. The Earl of Wessex's first public appearance was after the Trooping the Colour ceremony in 1964 when The Queen, carrying him in her arms, stood on the balcony of Buckingham Palace and showed her youngest son to the huge crowd outside.