The Great Fire of London died out on September 5, 1666, after raging 3 days.

…;but, Lord! what sad sight it was by moone-light to see, the whole City almost on fire, that you might see it plain at Woolwich, as if you were by it. 
Samuel Pepys, writing in his diary Wed. Sept. 5, 1666

Fire starts in Pudding Lane
The fire spreads rapidly
Houses are demolished to stop the fire
St. Paul’s Cathedral was destroyed
People are gathering in Moorfields
New plans to rebuild the city
Series: 350th Anniversary of The Great Fire of London
Issued 2016 by Royal Mail
Designed by The Chase

Samuel Pepys wrote about the fire in his diaries, and offers one of the best contemporary accounts of the 3 day conflagration. 

(Lord’s day). Some of our mayds sitting up late last night to get things ready against our feast to-day, Jane called us up about three in the morning, to tell us of a great fire they saw in the City. So I rose and slipped on my nightgowne, and went to her window, and thought it to be on the backside of Marke-lane at the farthest; but, being unused to such fires as followed, I thought it far enough off; and so went to bed again and to sleep. 
Sept. 2

On awakening at 7 am, Pepys discovered the fire had already consumed 300 buildings and raging out of control, hoping from one wooden building to the next. He dressed and walked to the Tower of London, one of the highest points in the city to see the size of the fire, “and there I did see the houses at that end of the bridge all on fire, and an infinite great fire on this and the other side the end of the bridge”.

While at the Tower, Pepys was told how the fire began:

… tells me that it begun this morning in the King’s baker’s house in Pudding-lane, and that it hath burned St. Magnus’s Church and most part of Fish-street already. So I down to the water-side, and there got a boat and through bridge, and there saw a lamentable fire. Poor Michell’s house, as far as the Old Swan, already burned that way, and the fire running further, that in a very little time it got as far as the Steeleyard, while I was there. Everybody endeavouring to remove their goods, and flinging into the river or bringing them into lighters that layoff; poor people staying in their houses as long as till the very fire touched them, and then running into boats, or clambering from one pair of stairs by the water-side to another.
Sun. Sept. 2, 1666

Within an hour Pepys wrote how the fire raged “every way, and nobody, to my sight, endeavouring to quench it”. He quickly rushed to White Hall pleading for action. If any of the city was to survive houses needed to be pulled down immediately to create a fire barrier. On the King’s command, Pepys was directed to instruct the Lord Mayor of London to begin the tear down. 

At last met my Lord Mayor in Canningstreet, like a man spent, with a handkercher about his neck. To the King’s message he cried, like a fainting woman, “Lord! what can I do? I am spent: people will not obey me. I have been pulling down houses; but the fire overtakes us faster than we can do it.” That he needed no more soldiers; and that, for himself, he must go and refresh himself, having been up all night. So he left me, and I him, and walked home, seeing people all almost distracted, and no manner of means used to quench the fire.  
Sun. Sept. 2, 1666

A warm wind aggravated the situation, fanning the flames to an uncontrollable level. The streets were jammed with people moving their belongings out of danger, and little done to stop the fire. By night, Pepys returned home and lamented on the conditions in the city and the “horrid noise the flames made, and the cracking of houses at their ruins.”

At 4am, Pepys was once again awake, this time to move “all my money, and plate, and best things” to safety. Among the valuables Pepys moved were his papers, wines and “Parmazan cheese”. By Tues, soldiers were blowing up streets, in a desperate attempt to form larger fire breaks. Pepys, his wife and his friends dined that evening at his office, away from the fire, watching its progress. 

This night Mrs. Turner (who, poor woman, was removing her goods all this day, good goods into the garden, and knows not how to dispose of them), and her husband supped with my wife and I at night, in the office; upon a shoulder of mutton from the cook’s, without any napkin or any thing, in a sad manner, but were merry. Only now and then walking into the garden, and saw how horridly the sky looks, all on a fire in the night, was enough to put us out of our wits; and, indeed, it was extremely dreadful, for it looks just as if it was at us; and the whole heaven on fire. 
Tues. Sept. 4, 1666

Early Wednesday morning, Pepys was awakened again with fresh reports of the fire spreading.

About two in the morning my wife calls me up and tells me of new cryes of fire, it being come to Barkeing Church, which is the bottom of our lane. I up, and finding it so, resolved presently to take her away, and did, and took my gold, which was about 2350l., W. Hewer, and Jane, down by Proundy’s boat to Woolwich; but, Lord! what sad sight it was by moone-light to see, the whole City almost on fire, that you might see it plain at Woolwich, as if you were by it.
Wed. Sept. 5, 1666