1973

3 January - The Queen attends a gala in honour of Britain's entry into the Common Market.

3 April - President de Echeverria of Mexico stays with The Queen and Prince Philip at Windsor Castle for his State Visit to the UK.

12 June - General Gowon of Nigeria arrives in the UK for his State Visit.

1-4 August - The Queen visits the Commonwealth Heads of Government conference abroad for the first time, in Ottawa, Canada.

20 October - The spectacular Sydney Opera House is officially opened by The Queen.

14 November - Princess Anne marries Captain Mark Phillips at Westminster Abbey.