Europe's oldest man, Henry Allingham, will reach 111 years, 11 months and 11 days today - a symbolic reference to the official ending of the First World War at the 11th hour on the 11th day of the 11th month.
It will signify another landmark for Mr Allingham, the last founder member of the RAF, whose life has spanned three centuries and six monarchs.
Mr Allingham, who lives at St Dunstan's care home for blind ex-service personnel in Ovingdean, near Brighton, East Sussex, will celebrate his 112th birthday with a fly-past at RAF Cranwell in Lincolnshire on June 6 - D-Day.
Graham Stark, of the First World War Veterans' Association, said: "The significance of Henry is not just his great age but the fact that he is literally history on legs. He saw the First World War from all theatres of war: from, sea, air and land."
Mr Allingham is just one of three known UK survivors from the First World War.
The other two are ex-Royal Navy stoker Bill Stone, 107, who was born in Devon but now living in Oxfordshire, and 109-year-old Harry Patch, who lives in Wells, Somerset, the last surviving Tommy to have served on the Western Front.
The Government announced two years ago that the death of the last known First World War veteran would be marked by a national memorial service at Westminster Abbey.
The decision was warmly welcomed by veterans and by MPs who have campaigned for a service to mark the final passing of the generation who fought in the 1914-18 conflict.
It was said the service would reflect the events of November 11, 1920, when the unknown warrior was laid to rest and the Cenotaph unveiled in Whitehall.
Mr Allingham, who has five grandchildren and 12 great grandchildren, joined the Royal Naval Air Service in September 1915 before transferring to the RAF in April 1918.
As well as being the last founder member of the RAF, he is also the sole survivor of the Battle of Jutland.
On what lessons he learnt from the First World War, Mr Allingham has said: "Hear all, see all and say nowt."
He has been awarded a string of accolades including the British War Medal, Victory Medal and the Legion d'honneur, France's highest military honour.
In April 2006 he was given the freedom of Eastbourne, the East Sussex seaside town where he retired to in the 60s.
He lived a relatively independent life alone in the resort but with his eyesight fast deteriorating, he moved to St Dunstan's where he can receive round-the-clock care.