I first went into the huge building that's now the science adventure centre, Magna, in the autumn of 1957. It was Steel Peech and Tozer's Templeborough Melting Shop then.
Not long out of National Service, I worked in the sales department, helping to market railway engine wheels and axles that had started life as steel ingots, in what was then the biggest open-hearth melting shop in Europe.
In its heyday, Templeborough dealt in molten steel, hundreds of tons pouring from the furnaces at a time, in rivers too bright to look at. Men with dark goggles guided and tended the dangerous work.
You think burning your hand in the oven is bad? How about being splashed by carelessly handled liquid steel at 1,600 degrees centigrade?
The years passed. I left to become a teacher. The works shrank, and closed in 1993. Now, after five years of development, it's alive again, as Magna.
I went back 45 years on, to satisfy my curiousity and show my grandson, George, part of my youth. The latter objective had to be abandoned. For whatever Magna is, it certainly isn't a steelmaking heritage centre.
The building, however, has been wonderfully used. Last autumn it won the prestigious RIBA Stirling Prize, the top UK architecture award. But it is effectively a dramatic backdrop for the interactive science exhibits in four pavilions on the themes Earth, Air, Fire and Water. You reach the pavilions on a suspended walkway that takes you through the middle of the dark vastness of the building.
The size and gloom overawed George at first, and all the background noises and lights. As the Stirling judges said: "Photographs cannot convey the feeling of being inside. The drama of being a small person within a vast black space, relieved by gashes of red light, sheets of flame and spots of white light, has to be experienced."
This in itself is enough to make the visit worthwhile for many people. Most children, however, will head for the science pavilions.
George liked them all, particularly Air, housed in what looks like a dirigible balloon, and Water, which almost immerses you in the stuff. When you're five, it must be difficult to think of anything better than shooting a powerful water cannon apparently straight at unsuspecting adults.
All in all this is a great place, and I am not surprised it has exceeded all visitor number forecasts.
There is a good, and still developing, educational programme, with materials and workshops around national curriculum science and technology themes. A computer suite has just been added.
Above all, it's a place different from anything else - much more than a museum, even something of a theme park, with a fun approach to science.
As you go round, all the time, brooding in the darkness overhead and far away to the sides, there's this huge grey shadowy building, a constant ghostly reminder that once upon a time thousands of men sweated out their working lives here.
ContactMagna, Sheffield Road, Templeborough, Rotherham, South Yorkshire S60 1DX. Tel: 01709 720002. Email: firstname.lastname@example.org Web: www.magnatrust.org.uk Cost: pound;3 per pupil, workshops pound;1.25 to pound;2 per pupil, teachers free with pupils.