Firefighters were quick to react in numbers when the alarms went off at Grosvenor Museum .
Five engines from Chester, Ellesmere Port and Powey Lane descended on the scene at midday on Monday (April 3).
Grosvenor Street was taped off and everyone inside the museum was safely evacuated.
It turned out the smoke was coming from a light fitting. There has been no damage to anything inside.
So why was the response so large?
A Cheshire Fire and Rescue Service spokeswoman said the much-loved museum was one of a number of buildings in Chester which had a 'pre-determined attendance'.
These are usually designated priority buildings in populated areas where the blaze could spread.
The spokeswoman added: "It may seem like overkill, but it's better to be safe than sorry."
Cheshire West and Chester Council said all staff and visitors were evacuated to a safe distance.
The incident cut short some school trips with children among those who had to be evacuated.
Emergency services had left Grosvenor Street by about 1pm - the museum reopened just before 3pm.
CWaC director of places strategy Alison Knight said:“All staff and visitors, including a group of schoolchildren, were calmly and safely evacuated when the fire alarm sounded and I would like to thank everyone for their co-operation and understanding.
“I would also like to thank the staff at the nearby Military Museum who helped out by hosting the school group during the temporary closure.
“There has been no damage to the museum or its contents and the building has been declared safe.”
A grade-II listed building, the Grosvenor dates back to 1886 and is home to thousands of priceless pieces of history.
The Cheshire Fire spokeswoman added: “A light fitting is believed to have been the cause of burning at a Chester museum.
“Firefighters wearing breathing apparatus searched the building and, finding the source, isolated the fitting and removed it from the ceiling.”
Grosvenor Museum had held some firefighter training exercises in 2015 which included a 'salvage plan' to save treasured artefacts in the event of a blaze.
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