The Queen will become the longest serving monarch in British history on Wednesday, September 9, overtaking the record previously held by her great-great-grandmother Queen Victoria.
Over the past 63 years the Queen has been helped by the people of Wales - from the Welsh Guards who keep her palaces safe, to the corgi enthusiasts who help her breed her Pembrokeshire corgis.
In 1992, Mary Davies from South Wales was picked to help the Queen breed corgi puppies:
As a show of Her Majesty's appreciation, Mary was given one of the puppies.
As well as helping the Queen in her personal life, when it comes to visiting Wales there is a big team of people ready to help. Organised by the Lord-Lieutenants they arrange visits for members of the Royal Family.
Captain Sir Norman Lloyd-Evans was Lord-Lieutenant of South Glamorgan and remembers many fond visits to Cardiff and the Vale of Glamorgan:
Watch Megan Boot's report: