As you reach the top of the stairs of Guildhall Art Gallery, a great canvas rising from the far wall immediately catches your eye.
Measuring 3.02m by 7.62m (that's the length of over four average height men), John Singleton Copley's The Defeat of the Floating Batteries at Gibraltar is, the Guildhall's curators believe, the biggest oil on canvas on display in the UK.
The dramatic scene recounts (with artistic licence) the British seeing off French and Spanish troops at Gibraltar, during the war of American independence, in 1782. Copley, ironically, was an American, and was therefore essentially depicting the humiliation of his allies.
So huge is the painting, that when it was reinstalled — having been rolled up and shipped out to the country just weeks before the previous gallery was bombed during the second world war — the 1960s gallery was specifically designed to accommodate it, hence the large balcony drop on the main level.
How long did it take to complete such a gargantuan masterpiece? The answer is two years. And then another seven.
Copley's first attempt was handed back to him by those who commissioned it, with heavy edits.
Explains Guildhall Gallery curator Katty Pearce, "The City Corporation felt it didn't emphasise the military aspects of the victory.
"It looked more like a Navy operation than it was, because he'd focused on dramatic/romantic elements of the sailors drowning, the British Navy rescuing Spanish sailors against a background of burning ships."
Copley's repaint was made all the more troublesome because his subjects were now scattered over Europe. It took him another seven years — and some serious travel expenses — to locate military commanders spread over the likes of Prussia and Germany.
This left the artist significantly out of pocket. But he had an idea to claw some of the cash back.
In 1791, Copley had an 84ft-long tent erected in Green Park, exhibiting the picture at an entrance fee of a shilling a head; perhaps the equivalent of paying a tenner today to watch the latest blockbuster action movie.
Having spent some time in Gibraltar, the painting is now a permanent exhibit at the Guildhall — dominating the space with its melodrama. So dominating is it, the staff sometimes cover it up, so that other exhibits can enjoy the limelight.
See The Defeat of the Floating Batteries at Gibraltar at Guildhall Art Gallery any day of the week. Entry is free.