A pub, fast food restaurant and nearby buildings were evacuated this afternoon after the roof of a historic 16th century pub caught fire.
A number of crews rushed to the city centre at around 2.15pm to douse the flames on the roof of The Westgate bar.
It is believed the fire started in the roof where builders were laying bitumen.
Nearby businesses have been evacuated and people ushered towards The Cross.
Bar manager Chris Marsh is said to have tried tackling the fire single-handedly before fire crews arrived.
Hundreds of on-lookers stopped as fire crews lifted a crane above the pub to put out the blaze.
Tom Skinner, from Gloucester city MP Richard Graham's office, which is nearby, said: "We could smell smoke and ran around the back where we saw that the roof was on fire.
"Chris, the manager, had blood on his arms and was apparently trying to tackle the fire before firefighters arrived."
Robin Ledbury, owner of The Barbers, which is two doors down, discovered the fire and called 999. He said: "It has all happened so quickly."
Two crews from Gloucester North and Gloucester South initially responded to the call after flames took over at The Westgate pub in Westgate Street, Gloucester just after 2pm.
After quickly assessing the risk, three further engines were called from Cheltenham East, Cheltenham West and Stroud, alongside an aerial appliance.
The 16th century pub, at the gateway to Gloucester's famous Cathedral, was well alight and, because it is an old building, the fear was that the fire could have easily spread to neighbouring properties.
The fire was brought under control at 3.10pm and at 5pm fire crews were still in attendance as part of a salvage operation.
More than 20 per cent of the roof was damaged by the fire.
Chief Fire Officer Jon Hall said: "This was a great opportunity to show just how quickly and efficiently fire crews work in the county – in this case ensuring a potentially dangerous situation was avoided.
"The aerial appliance was put to good use and shows that we have plenty of tools at our disposal to deal with emergencies as they arise."
Will Windsor-Clive, Cabinet member for communities, said: "I'm delighted the service was so quick to react to this particularly dangerous situation. Any significant damage would have been hugely detrimental to this historic part of the city centre. Speed was of the essence and it is thanks to our quick-thinking crews that a bad fire didn't become much worse."