Hull is a fine city, in selected parts only. It houses playwright John Godber, the excellent Ferens Art Gallery and Wilberforce Museum among much else. But it is fair to say that it has a bit of an image problem. The problem being that it doesn’t have an image. Moreover, there is nothing that you’d want to take children to on a wet Sunday. So Sir Terry Farrell’s latest building, The Deep (described as a “submarium” to distinguish it from mere two-a-penny aquaria) has to do for Hull at least a little of what Frank Gehry’s Guggenheim did for Bilbao, mixed with a lot of what the science-based Magna centre is doing for Rotherham.

People don’t go to Hull unless they have business there. That much used to be true also of Bilbao and Rotherham. Hull is stuck out on a limb in the very east of the north, on the immense Humber Estuary. Its surrounding landscape is reminiscent of Holland, right down to the hectares of glasshouses, the ubiquity of water and the huge skies. The local population is relatively small. All these things recommended it greatly to the reclusive late poet Philip Larkin when he chose to live there, but they ring warning bells when it comes to getting people into a big new visitor attraction there.

But if any single building can do the business for Hull, it ought to be this one. Because Hull has always had plenty to do with the sea. The original idea was to build a Natural History Museum of the north, but then the idea was refined: instead, why not do one thing very well, something that the Natural History Museum is weak on? Namely, the oceans?

So there are plenty of fish in The Deep, from tiny brightly-coloured tropical ones to scary great sharks, all in enormous acrylic tanks with some very convincing underwater scenery. You’d swear the coral was real. You will even be able to ride through the biggest tank - 35 feet deep - in a transparent lift when it finally opens to the public on March 25 for the Easter holidays. But the fish and the tanks are only part of the story it tells, which is to do with everything about the world’s oceans. This is not quite the architectural equivalent of David Attenborough’s recent “Blue Planet” TV series, but that gives you a flavour of it.