Almost 12 hours later at 11.03pm, after 36 pumping appliances from Berkshire, Oxfordshire, London, Buckinghamshire and Surrey, seven specialist units, 25 officers and more than 200 firefighters used more than one million gallons of litre to fight the fire, the stop message was sent out.
The fire, itself not fully out until 2.30am the next day, destroyed more than 100 rooms, covering an area of 7,000sqm.
It is thought the fire started when a spotlight ignited a candle in The Queen's Private Chapel before spreading and engulfing State Apartments including St George's Hall and The Chester and Brunswick Towers.
It was not just firefighters involved in the operation to tackle the flames as police, Castle staff, members of the Royal Household and men from the Household Cavalry, based at Combermere Barracks, helped save precious items held inside the Castle.
There were no serious injuries or deaths as a result of the fire and many pieces of art and furniture were saved either by them being moved from the Castle or by the fortunate fact that the seven most severely damaged rooms had been largely emptied the previous day for rewiring.
The damage the fire caused required £36.5m worth of restoration work, funded by Her Majesty, donations and charges from granting the public entry to the Castle precincts and Buckingham Palace - the first time the Palace was opened to the public.
The final structural stage of the restoration was completed in May 1996 while the final fitting out occurred three days before the fifth anniversary of the fire on November 17, 1997.
Twenty years on, people closely involved or effected by the fire have spoken to The Observer about their memories of the blaze.
See The Observer tomorrow for their stories and news about the future of Windsor fire station.
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