To mark the occasion, the Royal Navy will fire a 21-gun salute from Fort Blockhouse at Gosport at the entrance to Portsmouth Harbour.
Four specialist gunnery instructors from HMS Collingwood, in Fareham, will lead the ceremony at noon.
Commander David Hilton, base services manager at Portsmouth Naval Base, said: ‘It is tradition for the Royal Navy to mark important anniversaries of the Royal Family in this way.’
Keeping with tradition, ships in the naval base will be fully decked with colourful flags.
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The custom of navy gun salutes dates back to the early days of sail when ships visiting foreign ports would fire their guns before entering, proving they were empty and the visit was peaceful.
The portable 19th-century gun at Fort Blockhouse has been firing salutes since acquired by the navy in 1957.