This was the style science-fiction would adopt for the next 15 years, untill it began to look like an outdated past-future idea that spoke of large planetary bureaucracies.
The circular structure under the heliport was the Top of the Fair, a restaurant and cocktail bar. Surely there was more than that; I mean, that thing's huge. Perhaps most of it was steel structure to keep it from collapsing. Steel and concrete, of course. The materials of tomorrow!