The external columns gave the towers a look reminiscent of pinstripe power suits, but it was more than a stylistic choice. Fewer interior steel columns meant more rentable space on each acre-sized office floor. Some internal columns were still necessary, so the engineers clustered them in the inner boxes, known as the central core, among the elevators, stairwells, and utility shafts. The result was an extraordinary thirty thousand square feet9 of rentable, customizable space on nearly every office floor, uninterrupted by columns or walls, with incredible views to boot. Also, the narrow windows
...more
