A massive painting by the Italian baroque painter Luca Giordano, which narrowly survived the Coventry blitz, has been unveiled as building work nears completion on the redevelopment of the city’s Herbert Art Gallery.

The painting, Bacchus and Ariadne, which measures around 10 ft by 18 ft, was too large to be removed from the gallery while work on the £20 million refurbishment and extension was taking place, and it has been boarded up since the last phase began in 2005. The temperature and vibration inside its temporary cocoon has been checked every day for the last three years.

Painted in 1677 for the Rosso family in Florence, the painting depicts the Greek myth in which the hero Theseus sails away, abandoning Ariadne on the island of Naxos, but Bacchus, the god of wine and revelry, arrives to comfort her. Giordano (1634-1705) was a prolific artist who at one time was court painter to Charles II of Spain.

His nickname, “Luca fa-presto” (“Luke, work quickly”) reflects his prodigious work-rate but also the exhortations of his greedy father, who it is said would place food in his son’s mouth as he painted to save time on meal breaks. The painting was given to the city of Coventry by local MP Edward Ellice in 1855.

Ron Clarke, keeper of visual arts at The Herbert, says: “He hoped it would be the start of a collection for a new art gallery and one story says that Ellice received the painting as part payment of a gambling debt.

“It was hung in St Mary’s Hall from 1855 and then the city’s reference library which caught fire in the blitz. A hole was burned right through the painting and when it was cut out of its frame, it was rolled up too tightly and bent, which meant half the paint of Ariadne’s face flaked off and there were other losses.

“The painting was restored and hung in The Herbert when it was first opened in 1960.

“This is one of our most prized paintings and it is fantastic that it has now been uncrated and hung on the wall. It has remained in good condition during the last three years and we are delighted to see it once again in all its glory.”

The Giordano painting will be restored to pride of place in the old masters gallery when the Herbert’s refurbishment is completed this autumn.